Ketoconazole

updated

Ketoconazole shampoo has FDA approvals dating to 1985 for dandruff and tinea versicolor, and neither label makes a hair-loss claim. The hair-loss data are small and mostly uncontrolled, and hair density did not change in the one randomized 150-man trial. The anti-androgen effect is documented for oral dosing and cell culture, not for shampoo on the scalp, and oral ketoconazole carries a boxed warning for hepatotoxicity and QT prolongation.

Azole antifungal

  • FDA approved NIZORAL cream on 31 December 1985, NIZORAL 2% shampoo on 31 August 1990 and NIZORAL Anti-Dandruff 1% on 10 October 1997.
  • The over-the-counter label covers flaking, scaling and itching associated with dandruff and makes no hair-growth claim.
  • In 150 men with androgenic alopecia-related telogen effluvium and dandruff, 6 months of 1% ketoconazole shampoo left vertex hair density unchanged, with no unmedicated control.
  • Ketoconazole was not detected in plasma in 39 and 33 patients using the 2% shampoo long term, while a single oral dose lowered serum testosterone in young men.
  • Oral ketoconazole tablets carry a boxed warning for serious hepatotoxicity and QT prolongation, and on 25 July 2013 the EMA's CHMP recommended suspending them in the EU for fungal infections.
  • A PubMed search on 9 October 2026 returned 6 records on ketoconazole shampoo with androgen terms; none measured androgens on the scalp.

What is ketoconazole approved to do?

FDA-approved topical ketoconazole covers dandruff (1% over-the-counter shampoo) and tinea versicolor (2% shampoo), and neither label makes a hair-loss claim. Oral tablets are limited to serious systemic fungal infections and carry a boxed warning.

NIZORAL Anti-Dandruff is ketoconazole 1% shampoo, labeled to control flaking, scaling and itching associated with dandruff in adults and children 12 and older. The label version used here took effect on 10 September 2026, and it makes no hair-growth claim. The prescription 2% shampoo is labeled for tinea (pityriasis) versicolor, and its label makes no hair-loss claim either.

FDA approved NIZORAL tablets (NDA 018533) on 12 June 1981, NIZORAL cream (NDA 019084) on 31 December 1985 and NIZORAL 2% shampoo (NDA 019927) on 31 August 1990. All three are Janssen products now discontinued. NIZORAL Anti-Dandruff 1% (NDA 020310, Kramer) followed on 10 October 1997, and generic ketoconazole products are approved under ANDAs.

Oral ketoconazole tablets are a different regulatory product. They are not indicated for skin, nail or Candida infections and are limited to blastomycosis, coccidioidomycosis, histoplasmosis, chromomycosis and paracoccidioidomycosis when other therapy has failed or is not tolerated.

Ketoconazole is C26H28Cl2N4O4 (531.4 g/mol, CAS 65277-42-1). Levoketoconazole is a separate product (RECORLEV, NDA 214133, approved 30 December 2021) for endogenous hypercortisolemia in Cushing's syndrome, not for fungal infections. A NIZORAL-branded Hair Regrowth Treatment for Men contains minoxidil 5%, not ketoconazole.

NIZORAL Anti-Dandruff label, version effective 10 September 2026: dandruff use, no hair-growth claim

Official label

DailyMed, U.S. National Library of Medicine. NIZORAL Anti-Dandruff (ketoconazole 1%) shampoo, over-the-counter drug facts label, version effective 10 September 2026. Set ID a17b7424-ee7e-4fcc-b6b3-0904932ae319.

The over-the-counter label describes ketoconazole 1% shampoo as controlling flaking, scaling and itching associated with dandruff for adults and children 12 and older. It tells users to stop and ask a doctor if a rash appears or the condition worsens. The label makes no hair-growth claim.

Participants / model
Adults and children 12 and older with dandruff
Treatment
Ketoconazole 1% shampoo, topical
Follow-up
Label version effective 10 September 2026
Study design
Official label (OTC drug facts)
Funding
not stated in the source

The page gives no label directions. The label makes no claim about hair growth or hair loss.

Read the original source
Ketoconazole 2% shampoo label, version effective 31 May 2024: tinea versicolor, plasma levels, hair effects

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 2% shampoo, topical, prescribing information, label version effective 31 May 2024. Set ID 99da5233-2760-46f6-8fb3-d9df5da70bfb.

The label covers tinea (pityriasis) versicolor. Ketoconazole was not detected in plasma in 39 patients who shampooed 4 to 10 times a week for 6 months or in 33 patients who shampooed 2 to 3 times a week for 3 to 26 months. In 11 double-blind trials in 264 patients using it for dandruff or seborrheic dermatitis, an increase in normal hair loss and irritation occurred in less than 1%, and postmarketing reports include alopecia, hair discoloration and abnormal hair texture. The label suggests the drug impairs fungal ergosterol synthesis and makes no hair-loss claim.

Participants / model
Patients with tinea versicolor; shampoo PK and safety participants
Treatment
Ketoconazole 2% shampoo, topical
Follow-up
Label version effective 31 May 2024; plasma checks for 6 months and for 3 to 26 months
Study design
FDA prescribing information
Funding
not stated in the source

The page gives no label directions. The label makes no hair-loss claim.

Read the original source
Drugs@FDA: tablets 1981, cream 1985, 2% shampoo 1990, 1% OTC shampoo 1997

Regulatory record

U.S. Food and Drug Administration. Drugs@FDA application record for NDA 019927 (NIZORAL 2% shampoo), with related applications NDA 018533, NDA 019084, NDA 020310 and NDA 214133. Dates read from the openFDA Drugs@FDA records.

FDA approved NIZORAL tablets (NDA 018533) on 12 June 1981, NIZORAL cream (NDA 019084) on 31 December 1985 and NIZORAL 2% shampoo (NDA 019927) on 31 August 1990, all Janssen products now discontinued, and NIZORAL Anti-Dandruff 1% (NDA 020310, Kramer) on 10 October 1997. Generic ketoconazole products are approved under ANDAs. Levoketoconazole is a separate product (RECORLEV, NDA 214133, approved 30 December 2021).

Participants / model
Not a clinical population
Treatment
Drug applications
Follow-up
Approvals from 1981 to 2021
Study design
FDA application records
Funding
not stated in the source

These records give approval dates and status. Indications come from the product labels.

Read the original source
Ketoconazole tablet label, version effective 17 December 2025: boxed warning, indication limits, PK

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 200 mg oral tablets, prescribing information, label version effective 17 December 2025. Set ID 6d4be760-c723-4f54-a854-12c61cf91703.

Oral ketoconazole tablets carry a boxed warning for serious hepatotoxicity, including fatal cases and cases needing liver transplantation, some in patients without liver risk factors, and for QT prolongation through drug interactions. They are not indicated for skin, nail or Candida infections and are limited to blastomycosis, coccidioidomycosis, histoplasmosis, chromomycosis and paracoccidioidomycosis when other therapy has failed or is not tolerated; they are contraindicated in acute or chronic liver disease. Hepatotoxicity has followed both high doses for short periods and low doses for long periods. Adrenal corticosteroid secretion falls with oral dosing. Serum testosterone is lowered, impaired at 800 mg a day and abolished at 1,600 mg a day, with possible gynecomastia, impotence and oligospermia. A single 200 mg dose with a meal gives mean peak plasma levels of about 3.5 mcg/mL within 1 to 2 hours.

Participants / model
Patients with systemic fungal infections
Treatment
Ketoconazole 200 mg oral tablets
Follow-up
Label version effective 17 December 2025
Study design
FDA prescribing information
Funding
not stated in the source

These are oral, systemic effects; the shampoo label reports no detectable plasma drug. The page gives no label dosing.

Read the original source
PubChem CID 47576: C26H28Cl2N4O4, 531.4 g/mol

Chemical identity record

National Center for Biotechnology Information. PubChem Compound Summary for CID 47576, ketoconazole.

Ketoconazole: PubChem CID 47576, C26H28Cl2N4O4, 531.4 g/mol, CAS 65277-42-1. The US tablet label describes the drug as the (+/-)-cis racemate. Levoketoconazole (RECORLEV) is the 2S,4R enantiomer, approved for endogenous hypercortisolemia in Cushing's syndrome and not for fungal infections, with its own hepatotoxicity and QT boxed warning. A NIZORAL-branded Hair Regrowth Treatment for Men contains minoxidil 5%, not ketoconazole.

Participants / model
Chemical identity, not a clinical population
Treatment
Defined molecule; product identity
Follow-up
Not applicable
Study design
NLM chemical record
Funding
not stated in the source

Identity record only; it says nothing about efficacy or safety. The PubChem stereo naming for this record needs a second look on the record page.

Read the original source

What did the hair-loss studies find?

The studies are small and mostly uncontrolled. In the one randomized trial, 150 men using 1% ketoconazole shampoo for 6 months had no change in vertex hair density, and there was no unmedicated control.

In 150 men with telogen effluvium related to androgenic alopecia plus dandruff, randomized to 1% ketoconazole, 1% piroctone olamine or 1% zinc pyrithione shampoo 2 to 3 times a week for 6 months, vertex hair density was unchanged. Shedding fell 17.3%, 16.5% and 10.1%, and anagen percentage rose 4.9%, 7.9% and 6.8%. Mean hair shaft diameter rose 5.4% and 7.7% with ketoconazole and piroctone olamine and fell 2.2% with zinc pyrithione. There was no unmedicated control, and piroctone olamine performed comparably to ketoconazole.

A small study compared 2% ketoconazole shampoo with an unmedicated shampoo, with or without 2% minoxidil, in androgenic alopecia. Hair density, hair size and the proportion of anagen follicles improved almost similarly with the ketoconazole and minoxidil regimens, and casual sebum appeared lower with ketoconazole. The abstract does not give the number of participants, and the authors said clinical significance awaited a larger controlled study.

A systematic review of topical ketoconazole for androgenetic alopecia included five human studies (318 participants) and two mouse studies (40 animals). The human studies reported larger hair shaft diameter, one reported a higher pilary index, and photographic and subjective assessments improved. The authors concluded that randomized controlled trials are needed.

150 men, 6 months: hair density unchanged, no unmedicated control

Randomized controlled trial

Piérard-Franchimont C et al. Int J Cosmet Sci. 2002;24(5):249-56. PMID 18498517.

Vertex hair density was unchanged. Shedding fell 17.3%, 16.5% and 10.1%; anagen percentage rose 4.9%, 7.9% and 6.8%; and mean hair shaft diameter rose 5.4% and 7.7% with ketoconazole and piroctone olamine and fell 2.2% with zinc pyrithione. Piroctone olamine performed comparably to ketoconazole.

Participants / model
150 men with androgenic alopecia-related telogen effluvium and dandruff
Treatment
Ketoconazole 1%, piroctone olamine 1% or zinc pyrithione 1% shampoo, 2 to 3 times a week
Follow-up
6 months
Study design
Randomized comparison of three anti-dandruff shampoos
Funding
not stated in the source

There was no unmedicated control. Endpoints were hair density, shedding, anagen percentage, shaft diameter and sebum.

Read the original source
Small comparison: ketoconazole shampoo versus minoxidil, participant number not stated

Human study

Piérard-Franchimont C et al. Dermatology. 1998;196(4):474-7. PMID 9669136.

Hair density, hair size and the proportion of anagen follicles improved almost similarly with the ketoconazole and minoxidil regimens, and casual sebum appeared lower with ketoconazole. The abstract does not give the number of participants, and the authors said clinical significance awaited a larger controlled study.

Participants / model
People with androgenic alopecia (number not stated in the abstract)
Treatment
Ketoconazole 2% shampoo compared with an unmedicated shampoo, with or without minoxidil 2%
Follow-up
not stated in the source
Study design
Original comparative clinical study
Funding
not stated in the source

Endpoints were hair density, hair size, anagen proportion and sebum. The participant count needs the full text.

Read the original source
Systematic review: 5 human studies (318 participants) and 2 mouse studies

Systematic review and meta-analysis

Fields JR et al. Dermatol Ther. 2020;33(1):e13202. PMID 31858672.

The review included five human studies (318 participants) and two mouse studies (40 animals). The human studies reported larger hair shaft diameter, one reported a higher pilary index, and photographic and subjective assessments improved; the authors concluded that randomized controlled trials are needed.

Participants / model
Five human studies and two mouse studies
Treatment
Topical ketoconazole, mostly shampoo
Follow-up
not stated in the source
Study design
Systematic review
Funding
not stated in the source

Endpoints were hair shaft diameter, pilary index and photographic assessment.

Read the original source

What does the research show for seborrheic dermatitis?

A Cochrane review found 2% topical ketoconazole gave a 31% lower risk of failed clearance than placebo at four weeks, from low-quality evidence. It is evidence for seborrheic dermatitis, not hair loss.

A Cochrane review of topical antifungals for seborrheic dermatitis included 51 studies with 9,052 participants, among them 12 ketoconazole trials (3,253 participants) against placebo or vehicle. Topical ketoconazole 2% gave a 31% lower risk of failed clearance than placebo at four weeks (RR 0.69, 95% CI 0.59 to 0.81; 8 studies; low-quality evidence).

Remission was similar to topical steroids (RR 1.17, 95% CI 0.95 to 1.44), with fewer side effects than steroids (RR 0.56, 95% CI 0.32 to 0.96). These results apply to seborrheic dermatitis. They do not show an effect on hair loss.

Cochrane review: 51 studies, 12 ketoconazole trials, 3,253 participants

Systematic review and meta-analysis

Okokon EO et al. Cochrane Database Syst Rev. 2015(5):CD008138. PMID 25933684.

The review included 51 studies with 9,052 participants, among them 12 ketoconazole trials (3,253 participants) against placebo or vehicle. Topical ketoconazole 2% gave a 31% lower risk of failed clearance than placebo at four weeks (RR 0.69, 95% CI 0.59 to 0.81; 8 studies; low-quality evidence), remission similar to topical steroids (RR 1.17, 95% CI 0.95 to 1.44), and fewer side effects than steroids (RR 0.56, 95% CI 0.32 to 0.96).

Participants / model
People with seborrheic dermatitis in randomized trials
Treatment
Topical ketoconazole, mainly 2%
Follow-up
Clearance assessed at four weeks in the placebo comparison
Study design
Cochrane systematic review of randomized trials
Funding
not stated in the source

This is evidence for seborrheic dermatitis, not hair loss.

Read the original source

Is ketoconazole shampoo a supporting hair-loss agent through anti-inflammatory and mild anti-androgen effects?

As a supporting agent rather than a primary treatment, the framing fits the data, but the data are small. No study measured scalp or blood androgens in people using the shampoo, and the anti-inflammatory part was not tested separately.

Sellers describe ketoconazole shampoo as a supporting scalp agent in hair-loss protocols, through anti-inflammatory and mild anti-androgen effects, rather than a primary treatment.

The hair-loss data are small and mostly uncontrolled, and hair density did not change in the one randomized 150-man trial. That fits a supporting role at most. The anti-inflammatory part of the claim was not tested separately, and the seborrheic dermatitis data are not hair-loss data.

A PubMed search on 9 October 2026 for ketoconazole, shampoo and androgen terms returned 6 records: two clinical hair studies, a 15-patient pilot of a multi-drug regimen, two reviews and a hypothesis paper. None measured scalp or blood androgen levels or androgen-receptor activity in people using ketoconazole shampoo. A ClinicalTrials.gov search for ketoconazole alopecia the same day returned 2 records, a pazopanib drug-interaction study and a scalp-dermatitis shampoo trial with ketoconazole 2% as comparator, and neither studied hair loss.

The shampoo's mild anti-androgen effect is inferred from oral and cell data, not measured on the scalp.

PubMed search, 9 October 2026: 6 records, none measuring androgens on the scalp

PubMed search record

PubMed search run on 9 October 2026: ketoconazole AND shampoo AND (dihydrotestosterone OR testosterone OR androgen OR antiandrogen OR anti-androgenic). 6 records returned. A ClinicalTrials.gov search for "ketoconazole alopecia" run the same day returned 2 records.

The PubMed search returned 6 records: two clinical hair studies, a 15-patient pilot of a multi-drug regimen, two reviews and a hypothesis paper. None measured scalp or blood androgen levels or androgen-receptor activity in people using ketoconazole shampoo. The ClinicalTrials.gov search returned a pazopanib drug-interaction study and a scalp-dermatitis shampoo trial with ketoconazole 2% as comparator; neither studied hair loss. The shampoo's mild anti-androgen effect is inferred from oral and cell data, not measured on the scalp.

Participants / model
Records returned, not a population
Treatment
Not applicable
Follow-up
Searches run on 9 October 2026
Study design
Literature and registry search
Funding
not stated in the source

A search result shows what the databases returned on that date. It is not proof that no unindexed study exists.

Read the original source
150 men, 6 months: hair density unchanged, no unmedicated control

Randomized controlled trial

Piérard-Franchimont C et al. Int J Cosmet Sci. 2002;24(5):249-56. PMID 18498517.

Vertex hair density was unchanged. Shedding fell 17.3%, 16.5% and 10.1%; anagen percentage rose 4.9%, 7.9% and 6.8%; and mean hair shaft diameter rose 5.4% and 7.7% with ketoconazole and piroctone olamine and fell 2.2% with zinc pyrithione. Piroctone olamine performed comparably to ketoconazole.

Participants / model
150 men with androgenic alopecia-related telogen effluvium and dandruff
Treatment
Ketoconazole 1%, piroctone olamine 1% or zinc pyrithione 1% shampoo, 2 to 3 times a week
Follow-up
6 months
Study design
Randomized comparison of three anti-dandruff shampoos
Funding
not stated in the source

There was no unmedicated control. Endpoints were hair density, shedding, anagen percentage, shaft diameter and sebum.

Read the original source
Small comparison: ketoconazole shampoo versus minoxidil, participant number not stated

Human study

Piérard-Franchimont C et al. Dermatology. 1998;196(4):474-7. PMID 9669136.

Hair density, hair size and the proportion of anagen follicles improved almost similarly with the ketoconazole and minoxidil regimens, and casual sebum appeared lower with ketoconazole. The abstract does not give the number of participants, and the authors said clinical significance awaited a larger controlled study.

Participants / model
People with androgenic alopecia (number not stated in the abstract)
Treatment
Ketoconazole 2% shampoo compared with an unmedicated shampoo, with or without minoxidil 2%
Follow-up
not stated in the source
Study design
Original comparative clinical study
Funding
not stated in the source

Endpoints were hair density, hair size, anagen proportion and sebum. The participant count needs the full text.

Read the original source

Where does the anti-androgen effect come from?

From oral dosing and cell culture, not from shampoo. A single oral dose lowered serum testosterone in young men, and in cultured skin fibroblasts ketoconazole bound the androgen receptor only at a high concentration.

In a double-blind, placebo-controlled study in normal young men who took placebo, ketoconazole 200 mg and terbinafine 500 mg on three occasions in random order, the single oral ketoconazole dose caused a steep fall in serum testosterone, with a nadir at 4 to 5 hours and subnormal levels for about 8 to 9 hours, and a rise in 17-hydroxyprogesterone. Terbinafine had no such effect. The abstract does not give the number of men.

In cultured human skin fibroblasts, ketoconazole competed for androgen receptor binding with 50% displacement at 6.4 (SE 1.8) x 10^-5 M, and the author noted this concentration is not likely to be reached in vivo, at least in plasma. Of the imidazoles tested (with clotrimazole, miconazole and fluconazole), only ketoconazole interacted with the receptor. This supports a weak receptor interaction at high concentration, not a measured scalp effect from shampoo.

In male C3H/HeN mice, 2% ketoconazole in 95% ethanol applied daily for three weeks to clipped dorsal skin produced significantly more coat regrowth than vehicle (p < 0.01, n = 10), and repeat experiments agreed. The mechanism was unclear, and this is mouse coat regrowth, not human scalp hair.

Oral ketoconazole in young men: steep testosterone fall, nadir at 4 to 5 hours

Randomized controlled trial

Nashan D et al. Acta Endocrinol (Copenh). 1989;120(5):677-81. PMID 2499150.

The single oral ketoconazole dose caused a steep fall in serum testosterone with a nadir at 4 to 5 hours and subnormal levels for about 8 to 9 hours, with a rise in 17-hydroxyprogesterone; terbinafine had no such effect.

Participants / model
Normal young men (number not stated in the abstract)
Treatment
Single oral doses of ketoconazole 200 mg, terbinafine 500 mg or placebo on three occasions in random order
Follow-up
Single doses on three occasions
Study design
Double-blind, placebo-controlled study with random-order crossover
Funding
not stated in the source

This documented anti-androgen action comes from oral dosing. Endpoints were serum testosterone, 17-hydroxyprogesterone and LH pulses.

Read the original source
Cell study: weak androgen receptor competition at high concentration

Cell study

Eil C. Horm Metab Res. 1992;24(8):367-70. PMID 1526623.

Ketoconazole competed for androgen receptor binding with 50% displacement at 6.4 (SE 1.8) x 10^-5 M, and the author noted this concentration is not likely to be reached in vivo, at least in plasma. Of the imidazoles tested (with clotrimazole, miconazole and fluconazole), only ketoconazole interacted with the receptor.

Participants / model
Cultured human skin fibroblasts
Treatment
In-vitro ketoconazole
Follow-up
not stated in the source
Study design
Original laboratory study
Funding
not stated in the source

This supports a weak receptor interaction at high concentration, not a measured scalp anti-androgen effect from shampoo.

Read the original source
Mouse coat regrowth: 2% ketoconazole beat vehicle, n = 10

Animal study

Jiang J et al. J Dermatol. 2005;32(4):243-7. PMID 15863844.

Ketoconazole produced significantly more coat regrowth than vehicle (p < 0.01, n = 10), and repeat experiments agreed. The mechanism was unclear.

Participants / model
Male C3H/HeN mice
Treatment
Topical 2% ketoconazole in 95% ethanol, daily to clipped dorsal skin
Follow-up
3 weeks
Study design
Original animal study
Funding
not stated in the source

This is mouse coat regrowth, not human scalp hair.

Read the original source
Ketoconazole tablet label, version effective 17 December 2025: boxed warning, indication limits, PK

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 200 mg oral tablets, prescribing information, label version effective 17 December 2025. Set ID 6d4be760-c723-4f54-a854-12c61cf91703.

Oral ketoconazole tablets carry a boxed warning for serious hepatotoxicity, including fatal cases and cases needing liver transplantation, some in patients without liver risk factors, and for QT prolongation through drug interactions. They are not indicated for skin, nail or Candida infections and are limited to blastomycosis, coccidioidomycosis, histoplasmosis, chromomycosis and paracoccidioidomycosis when other therapy has failed or is not tolerated; they are contraindicated in acute or chronic liver disease. Hepatotoxicity has followed both high doses for short periods and low doses for long periods. Adrenal corticosteroid secretion falls with oral dosing. Serum testosterone is lowered, impaired at 800 mg a day and abolished at 1,600 mg a day, with possible gynecomastia, impotence and oligospermia. A single 200 mg dose with a meal gives mean peak plasma levels of about 3.5 mcg/mL within 1 to 2 hours.

Participants / model
Patients with systemic fungal infections
Treatment
Ketoconazole 200 mg oral tablets
Follow-up
Label version effective 17 December 2025
Study design
FDA prescribing information
Funding
not stated in the source

These are oral, systemic effects; the shampoo label reports no detectable plasma drug. The page gives no label dosing.

Read the original source

How does ketoconazole work, and what does the body do with it?

The shampoo label suggests ketoconazole impairs fungal ergosterol synthesis. After a single oral 200 mg dose with a meal, mean peak plasma levels were about 3.5 mcg/mL within 1 to 2 hours, and the shampoo label reports no detectable plasma drug.

The 2% shampoo label suggests the drug impairs fungal ergosterol synthesis and makes no hair-loss claim. The anti-inflammatory and anti-androgen mechanisms sellers cite are not established for shampoo on the scalp.

A single 200 mg oral dose with a meal gives mean peak plasma levels of about 3.5 mcg/mL within 1 to 2 hours. Ketoconazole was not detected in plasma in 39 patients who shampooed 4 to 10 times a week for 6 months or in 33 patients who shampooed 2 to 3 times a week for 3 to 26 months. A half-life is not given in the sources reviewed.

Ketoconazole 2% shampoo label, version effective 31 May 2024: tinea versicolor, plasma levels, hair effects

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 2% shampoo, topical, prescribing information, label version effective 31 May 2024. Set ID 99da5233-2760-46f6-8fb3-d9df5da70bfb.

The label covers tinea (pityriasis) versicolor. Ketoconazole was not detected in plasma in 39 patients who shampooed 4 to 10 times a week for 6 months or in 33 patients who shampooed 2 to 3 times a week for 3 to 26 months. In 11 double-blind trials in 264 patients using it for dandruff or seborrheic dermatitis, an increase in normal hair loss and irritation occurred in less than 1%, and postmarketing reports include alopecia, hair discoloration and abnormal hair texture. The label suggests the drug impairs fungal ergosterol synthesis and makes no hair-loss claim.

Participants / model
Patients with tinea versicolor; shampoo PK and safety participants
Treatment
Ketoconazole 2% shampoo, topical
Follow-up
Label version effective 31 May 2024; plasma checks for 6 months and for 3 to 26 months
Study design
FDA prescribing information
Funding
not stated in the source

The page gives no label directions. The label makes no hair-loss claim.

Read the original source
Ketoconazole tablet label, version effective 17 December 2025: boxed warning, indication limits, PK

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 200 mg oral tablets, prescribing information, label version effective 17 December 2025. Set ID 6d4be760-c723-4f54-a854-12c61cf91703.

Oral ketoconazole tablets carry a boxed warning for serious hepatotoxicity, including fatal cases and cases needing liver transplantation, some in patients without liver risk factors, and for QT prolongation through drug interactions. They are not indicated for skin, nail or Candida infections and are limited to blastomycosis, coccidioidomycosis, histoplasmosis, chromomycosis and paracoccidioidomycosis when other therapy has failed or is not tolerated; they are contraindicated in acute or chronic liver disease. Hepatotoxicity has followed both high doses for short periods and low doses for long periods. Adrenal corticosteroid secretion falls with oral dosing. Serum testosterone is lowered, impaired at 800 mg a day and abolished at 1,600 mg a day, with possible gynecomastia, impotence and oligospermia. A single 200 mg dose with a meal gives mean peak plasma levels of about 3.5 mcg/mL within 1 to 2 hours.

Participants / model
Patients with systemic fungal infections
Treatment
Ketoconazole 200 mg oral tablets
Follow-up
Label version effective 17 December 2025
Study design
FDA prescribing information
Funding
not stated in the source

These are oral, systemic effects; the shampoo label reports no detectable plasma drug. The page gives no label dosing.

Read the original source

What risks do the labels report for the shampoo and the tablets?

Oral tablets carry a boxed warning for serious hepatotoxicity, including fatal cases, and for QT prolongation through drug interactions. For the shampoo, the label reports no detectable plasma drug and irritation or increased normal hair loss in less than 1% in trials.

Oral ketoconazole tablets carry a boxed warning for serious hepatotoxicity, including fatal cases and cases needing liver transplantation, some in patients without liver risk factors, and for QT prolongation through drug interactions. They are contraindicated in acute or chronic liver disease, and hepatotoxicity has followed both high doses for short periods and low doses for long periods. Adrenal corticosteroid secretion falls with oral dosing. Serum testosterone is lowered, impaired at 800 mg a day and abolished at 1,600 mg a day, with possible gynecomastia, impotence and oligospermia.

For the shampoo, ketoconazole was not detected in plasma after long-term use in the label studies. In 11 double-blind trials in 264 patients using the 2% shampoo for dandruff or seborrheic dermatitis, an increase in normal hair loss and irritation occurred in less than 1%. Postmarketing reports include alopecia, hair discoloration and abnormal hair texture. The over-the-counter label tells users to stop and ask a doctor if a rash appears or the condition worsens.

In the Cochrane review of seborrheic dermatitis, topical ketoconazole 2% had fewer side effects than topical steroids (RR 0.56, 95% CI 0.32 to 0.96).

Ketoconazole tablet label, version effective 17 December 2025: boxed warning, indication limits, PK

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 200 mg oral tablets, prescribing information, label version effective 17 December 2025. Set ID 6d4be760-c723-4f54-a854-12c61cf91703.

Oral ketoconazole tablets carry a boxed warning for serious hepatotoxicity, including fatal cases and cases needing liver transplantation, some in patients without liver risk factors, and for QT prolongation through drug interactions. They are not indicated for skin, nail or Candida infections and are limited to blastomycosis, coccidioidomycosis, histoplasmosis, chromomycosis and paracoccidioidomycosis when other therapy has failed or is not tolerated; they are contraindicated in acute or chronic liver disease. Hepatotoxicity has followed both high doses for short periods and low doses for long periods. Adrenal corticosteroid secretion falls with oral dosing. Serum testosterone is lowered, impaired at 800 mg a day and abolished at 1,600 mg a day, with possible gynecomastia, impotence and oligospermia. A single 200 mg dose with a meal gives mean peak plasma levels of about 3.5 mcg/mL within 1 to 2 hours.

Participants / model
Patients with systemic fungal infections
Treatment
Ketoconazole 200 mg oral tablets
Follow-up
Label version effective 17 December 2025
Study design
FDA prescribing information
Funding
not stated in the source

These are oral, systemic effects; the shampoo label reports no detectable plasma drug. The page gives no label dosing.

Read the original source
Ketoconazole 2% shampoo label, version effective 31 May 2024: tinea versicolor, plasma levels, hair effects

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 2% shampoo, topical, prescribing information, label version effective 31 May 2024. Set ID 99da5233-2760-46f6-8fb3-d9df5da70bfb.

The label covers tinea (pityriasis) versicolor. Ketoconazole was not detected in plasma in 39 patients who shampooed 4 to 10 times a week for 6 months or in 33 patients who shampooed 2 to 3 times a week for 3 to 26 months. In 11 double-blind trials in 264 patients using it for dandruff or seborrheic dermatitis, an increase in normal hair loss and irritation occurred in less than 1%, and postmarketing reports include alopecia, hair discoloration and abnormal hair texture. The label suggests the drug impairs fungal ergosterol synthesis and makes no hair-loss claim.

Participants / model
Patients with tinea versicolor; shampoo PK and safety participants
Treatment
Ketoconazole 2% shampoo, topical
Follow-up
Label version effective 31 May 2024; plasma checks for 6 months and for 3 to 26 months
Study design
FDA prescribing information
Funding
not stated in the source

The page gives no label directions. The label makes no hair-loss claim.

Read the original source
NIZORAL Anti-Dandruff label, version effective 10 September 2026: dandruff use, no hair-growth claim

Official label

DailyMed, U.S. National Library of Medicine. NIZORAL Anti-Dandruff (ketoconazole 1%) shampoo, over-the-counter drug facts label, version effective 10 September 2026. Set ID a17b7424-ee7e-4fcc-b6b3-0904932ae319.

The over-the-counter label describes ketoconazole 1% shampoo as controlling flaking, scaling and itching associated with dandruff for adults and children 12 and older. It tells users to stop and ask a doctor if a rash appears or the condition worsens. The label makes no hair-growth claim.

Participants / model
Adults and children 12 and older with dandruff
Treatment
Ketoconazole 1% shampoo, topical
Follow-up
Label version effective 10 September 2026
Study design
Official label (OTC drug facts)
Funding
not stated in the source

The page gives no label directions. The label makes no claim about hair growth or hair loss.

Read the original source
Cochrane review: 51 studies, 12 ketoconazole trials, 3,253 participants

Systematic review and meta-analysis

Okokon EO et al. Cochrane Database Syst Rev. 2015(5):CD008138. PMID 25933684.

The review included 51 studies with 9,052 participants, among them 12 ketoconazole trials (3,253 participants) against placebo or vehicle. Topical ketoconazole 2% gave a 31% lower risk of failed clearance than placebo at four weeks (RR 0.69, 95% CI 0.59 to 0.81; 8 studies; low-quality evidence), remission similar to topical steroids (RR 1.17, 95% CI 0.95 to 1.44), and fewer side effects than steroids (RR 0.56, 95% CI 0.32 to 0.96).

Participants / model
People with seborrheic dermatitis in randomized trials
Treatment
Topical ketoconazole, mainly 2%
Follow-up
Clearance assessed at four weeks in the placebo comparison
Study design
Cochrane systematic review of randomized trials
Funding
not stated in the source

This is evidence for seborrheic dermatitis, not hair loss.

Read the original source

Why is oral ketoconazole restricted in the US and the EU?

The US label limits the tablets to serious systemic fungal infections, and on 25 July 2013 the EMA's CHMP recommended suspending oral ketoconazole in the EU for fungal infections because liver injury outweighed the benefits.

The US tablet label limits oral ketoconazole to five systemic fungal infections when other therapy has failed or is not tolerated. On 25 July 2013 the EMA's CHMP recommended suspending the marketing authorizations of oral ketoconazole throughout the EU for fungal infections, concluding that the risk of liver injury outweighed the benefits. Liver injury occurred early after starting recommended doses, and no measure could adequately reduce the risk.

The same review said topical ketoconazole formulations, including shampoos, have very low systemic absorption and may continue to be used as approved. Later steps in the EU procedure are not covered here.

Ketoconazole tablet label, version effective 17 December 2025: boxed warning, indication limits, PK

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 200 mg oral tablets, prescribing information, label version effective 17 December 2025. Set ID 6d4be760-c723-4f54-a854-12c61cf91703.

Oral ketoconazole tablets carry a boxed warning for serious hepatotoxicity, including fatal cases and cases needing liver transplantation, some in patients without liver risk factors, and for QT prolongation through drug interactions. They are not indicated for skin, nail or Candida infections and are limited to blastomycosis, coccidioidomycosis, histoplasmosis, chromomycosis and paracoccidioidomycosis when other therapy has failed or is not tolerated; they are contraindicated in acute or chronic liver disease. Hepatotoxicity has followed both high doses for short periods and low doses for long periods. Adrenal corticosteroid secretion falls with oral dosing. Serum testosterone is lowered, impaired at 800 mg a day and abolished at 1,600 mg a day, with possible gynecomastia, impotence and oligospermia. A single 200 mg dose with a meal gives mean peak plasma levels of about 3.5 mcg/mL within 1 to 2 hours.

Participants / model
Patients with systemic fungal infections
Treatment
Ketoconazole 200 mg oral tablets
Follow-up
Label version effective 17 December 2025
Study design
FDA prescribing information
Funding
not stated in the source

These are oral, systemic effects; the shampoo label reports no detectable plasma drug. The page gives no label dosing.

Read the original source
EMA CHMP, 25 July 2013: suspension of oral ketoconazole recommended; shampoos may continue

Regulatory record

European Medicines Agency. Ketoconazole-containing medicines, referral procedure page. CHMP recommendation of 25 July 2013.

On 25 July 2013 the EMA's CHMP recommended suspending the marketing authorizations of oral ketoconazole throughout the EU for fungal infections, concluding that the risk of liver injury outweighed the benefits; liver injury occurred early after starting recommended doses and no measure could adequately reduce the risk. The same review said topical ketoconazole formulations, including shampoos, have very low systemic absorption and may continue to be used as approved.

Participants / model
Patients treated for fungal infections in the EU
Treatment
Oral ketoconazole; topical formulations as the comparison
Follow-up
Recommendation of 25 July 2013
Study design
EMA regulatory benefit-risk decision
Funding
not stated in the source

This page reports the CHMP recommendation. Later steps in the procedure are not covered.

Read the original source

Why does ketoconazole sit in A tier?

More than 30 years of FDA approval for topical dandruff and skin uses, a Cochrane review in seborrheic dermatitis, and no detectable plasma drug after long-term shampooing support the A for the topical products. Hair-loss data are small and the oral form is a separate story.

The A applies to topical ketoconazole for its labeled uses. Hair-loss use runs wider than any label, the hair-loss data are small and mostly uncontrolled, and hair density did not change in the one randomized 150-man trial.

The anti-androgen effect is documented only for oral dosing and cell culture, not for shampoo on the scalp. The oral tablets are restricted to serious systemic fungal infections in the US and carry a boxed warning, and the CHMP recommended suspending them for fungal infections in the EU because of liver injury.

Drugs@FDA: tablets 1981, cream 1985, 2% shampoo 1990, 1% OTC shampoo 1997

Regulatory record

U.S. Food and Drug Administration. Drugs@FDA application record for NDA 019927 (NIZORAL 2% shampoo), with related applications NDA 018533, NDA 019084, NDA 020310 and NDA 214133. Dates read from the openFDA Drugs@FDA records.

FDA approved NIZORAL tablets (NDA 018533) on 12 June 1981, NIZORAL cream (NDA 019084) on 31 December 1985 and NIZORAL 2% shampoo (NDA 019927) on 31 August 1990, all Janssen products now discontinued, and NIZORAL Anti-Dandruff 1% (NDA 020310, Kramer) on 10 October 1997. Generic ketoconazole products are approved under ANDAs. Levoketoconazole is a separate product (RECORLEV, NDA 214133, approved 30 December 2021).

Participants / model
Not a clinical population
Treatment
Drug applications
Follow-up
Approvals from 1981 to 2021
Study design
FDA application records
Funding
not stated in the source

These records give approval dates and status. Indications come from the product labels.

Read the original source
Cochrane review: 51 studies, 12 ketoconazole trials, 3,253 participants

Systematic review and meta-analysis

Okokon EO et al. Cochrane Database Syst Rev. 2015(5):CD008138. PMID 25933684.

The review included 51 studies with 9,052 participants, among them 12 ketoconazole trials (3,253 participants) against placebo or vehicle. Topical ketoconazole 2% gave a 31% lower risk of failed clearance than placebo at four weeks (RR 0.69, 95% CI 0.59 to 0.81; 8 studies; low-quality evidence), remission similar to topical steroids (RR 1.17, 95% CI 0.95 to 1.44), and fewer side effects than steroids (RR 0.56, 95% CI 0.32 to 0.96).

Participants / model
People with seborrheic dermatitis in randomized trials
Treatment
Topical ketoconazole, mainly 2%
Follow-up
Clearance assessed at four weeks in the placebo comparison
Study design
Cochrane systematic review of randomized trials
Funding
not stated in the source

This is evidence for seborrheic dermatitis, not hair loss.

Read the original source
Ketoconazole 2% shampoo label, version effective 31 May 2024: tinea versicolor, plasma levels, hair effects

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 2% shampoo, topical, prescribing information, label version effective 31 May 2024. Set ID 99da5233-2760-46f6-8fb3-d9df5da70bfb.

The label covers tinea (pityriasis) versicolor. Ketoconazole was not detected in plasma in 39 patients who shampooed 4 to 10 times a week for 6 months or in 33 patients who shampooed 2 to 3 times a week for 3 to 26 months. In 11 double-blind trials in 264 patients using it for dandruff or seborrheic dermatitis, an increase in normal hair loss and irritation occurred in less than 1%, and postmarketing reports include alopecia, hair discoloration and abnormal hair texture. The label suggests the drug impairs fungal ergosterol synthesis and makes no hair-loss claim.

Participants / model
Patients with tinea versicolor; shampoo PK and safety participants
Treatment
Ketoconazole 2% shampoo, topical
Follow-up
Label version effective 31 May 2024; plasma checks for 6 months and for 3 to 26 months
Study design
FDA prescribing information
Funding
not stated in the source

The page gives no label directions. The label makes no hair-loss claim.

Read the original source
150 men, 6 months: hair density unchanged, no unmedicated control

Randomized controlled trial

Piérard-Franchimont C et al. Int J Cosmet Sci. 2002;24(5):249-56. PMID 18498517.

Vertex hair density was unchanged. Shedding fell 17.3%, 16.5% and 10.1%; anagen percentage rose 4.9%, 7.9% and 6.8%; and mean hair shaft diameter rose 5.4% and 7.7% with ketoconazole and piroctone olamine and fell 2.2% with zinc pyrithione. Piroctone olamine performed comparably to ketoconazole.

Participants / model
150 men with androgenic alopecia-related telogen effluvium and dandruff
Treatment
Ketoconazole 1%, piroctone olamine 1% or zinc pyrithione 1% shampoo, 2 to 3 times a week
Follow-up
6 months
Study design
Randomized comparison of three anti-dandruff shampoos
Funding
not stated in the source

There was no unmedicated control. Endpoints were hair density, shedding, anagen percentage, shaft diameter and sebum.

Read the original source
Ketoconazole tablet label, version effective 17 December 2025: boxed warning, indication limits, PK

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 200 mg oral tablets, prescribing information, label version effective 17 December 2025. Set ID 6d4be760-c723-4f54-a854-12c61cf91703.

Oral ketoconazole tablets carry a boxed warning for serious hepatotoxicity, including fatal cases and cases needing liver transplantation, some in patients without liver risk factors, and for QT prolongation through drug interactions. They are not indicated for skin, nail or Candida infections and are limited to blastomycosis, coccidioidomycosis, histoplasmosis, chromomycosis and paracoccidioidomycosis when other therapy has failed or is not tolerated; they are contraindicated in acute or chronic liver disease. Hepatotoxicity has followed both high doses for short periods and low doses for long periods. Adrenal corticosteroid secretion falls with oral dosing. Serum testosterone is lowered, impaired at 800 mg a day and abolished at 1,600 mg a day, with possible gynecomastia, impotence and oligospermia. A single 200 mg dose with a meal gives mean peak plasma levels of about 3.5 mcg/mL within 1 to 2 hours.

Participants / model
Patients with systemic fungal infections
Treatment
Ketoconazole 200 mg oral tablets
Follow-up
Label version effective 17 December 2025
Study design
FDA prescribing information
Funding
not stated in the source

These are oral, systemic effects; the shampoo label reports no detectable plasma drug. The page gives no label dosing.

Read the original source
EMA CHMP, 25 July 2013: suspension of oral ketoconazole recommended; shampoos may continue

Regulatory record

European Medicines Agency. Ketoconazole-containing medicines, referral procedure page. CHMP recommendation of 25 July 2013.

On 25 July 2013 the EMA's CHMP recommended suspending the marketing authorizations of oral ketoconazole throughout the EU for fungal infections, concluding that the risk of liver injury outweighed the benefits; liver injury occurred early after starting recommended doses and no measure could adequately reduce the risk. The same review said topical ketoconazole formulations, including shampoos, have very low systemic absorption and may continue to be used as approved.

Participants / model
Patients treated for fungal infections in the EU
Treatment
Oral ketoconazole; topical formulations as the comparison
Follow-up
Recommendation of 25 July 2013
Study design
EMA regulatory benefit-risk decision
Funding
not stated in the source

This page reports the CHMP recommendation. Later steps in the procedure are not covered.

Read the original source

Studies and sources

NIZORAL Anti-Dandruff label, version effective 10 September 2026: dandruff use, no hair-growth claim

Official label

DailyMed, U.S. National Library of Medicine. NIZORAL Anti-Dandruff (ketoconazole 1%) shampoo, over-the-counter drug facts label, version effective 10 September 2026. Set ID a17b7424-ee7e-4fcc-b6b3-0904932ae319.

The over-the-counter label describes ketoconazole 1% shampoo as controlling flaking, scaling and itching associated with dandruff for adults and children 12 and older. It tells users to stop and ask a doctor if a rash appears or the condition worsens. The label makes no hair-growth claim.

Participants / model
Adults and children 12 and older with dandruff
Treatment
Ketoconazole 1% shampoo, topical
Follow-up
Label version effective 10 September 2026
Study design
Official label (OTC drug facts)
Funding
not stated in the source

The page gives no label directions. The label makes no claim about hair growth or hair loss.

Read the original source
Ketoconazole 2% shampoo label, version effective 31 May 2024: tinea versicolor, plasma levels, hair effects

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 2% shampoo, topical, prescribing information, label version effective 31 May 2024. Set ID 99da5233-2760-46f6-8fb3-d9df5da70bfb.

The label covers tinea (pityriasis) versicolor. Ketoconazole was not detected in plasma in 39 patients who shampooed 4 to 10 times a week for 6 months or in 33 patients who shampooed 2 to 3 times a week for 3 to 26 months. In 11 double-blind trials in 264 patients using it for dandruff or seborrheic dermatitis, an increase in normal hair loss and irritation occurred in less than 1%, and postmarketing reports include alopecia, hair discoloration and abnormal hair texture. The label suggests the drug impairs fungal ergosterol synthesis and makes no hair-loss claim.

Participants / model
Patients with tinea versicolor; shampoo PK and safety participants
Treatment
Ketoconazole 2% shampoo, topical
Follow-up
Label version effective 31 May 2024; plasma checks for 6 months and for 3 to 26 months
Study design
FDA prescribing information
Funding
not stated in the source

The page gives no label directions. The label makes no hair-loss claim.

Read the original source
Drugs@FDA: tablets 1981, cream 1985, 2% shampoo 1990, 1% OTC shampoo 1997

Regulatory record

U.S. Food and Drug Administration. Drugs@FDA application record for NDA 019927 (NIZORAL 2% shampoo), with related applications NDA 018533, NDA 019084, NDA 020310 and NDA 214133. Dates read from the openFDA Drugs@FDA records.

FDA approved NIZORAL tablets (NDA 018533) on 12 June 1981, NIZORAL cream (NDA 019084) on 31 December 1985 and NIZORAL 2% shampoo (NDA 019927) on 31 August 1990, all Janssen products now discontinued, and NIZORAL Anti-Dandruff 1% (NDA 020310, Kramer) on 10 October 1997. Generic ketoconazole products are approved under ANDAs. Levoketoconazole is a separate product (RECORLEV, NDA 214133, approved 30 December 2021).

Participants / model
Not a clinical population
Treatment
Drug applications
Follow-up
Approvals from 1981 to 2021
Study design
FDA application records
Funding
not stated in the source

These records give approval dates and status. Indications come from the product labels.

Read the original source
Ketoconazole tablet label, version effective 17 December 2025: boxed warning, indication limits, PK

FDA prescribing information

DailyMed, U.S. National Library of Medicine. Ketoconazole 200 mg oral tablets, prescribing information, label version effective 17 December 2025. Set ID 6d4be760-c723-4f54-a854-12c61cf91703.

Oral ketoconazole tablets carry a boxed warning for serious hepatotoxicity, including fatal cases and cases needing liver transplantation, some in patients without liver risk factors, and for QT prolongation through drug interactions. They are not indicated for skin, nail or Candida infections and are limited to blastomycosis, coccidioidomycosis, histoplasmosis, chromomycosis and paracoccidioidomycosis when other therapy has failed or is not tolerated; they are contraindicated in acute or chronic liver disease. Hepatotoxicity has followed both high doses for short periods and low doses for long periods. Adrenal corticosteroid secretion falls with oral dosing. Serum testosterone is lowered, impaired at 800 mg a day and abolished at 1,600 mg a day, with possible gynecomastia, impotence and oligospermia. A single 200 mg dose with a meal gives mean peak plasma levels of about 3.5 mcg/mL within 1 to 2 hours.

Participants / model
Patients with systemic fungal infections
Treatment
Ketoconazole 200 mg oral tablets
Follow-up
Label version effective 17 December 2025
Study design
FDA prescribing information
Funding
not stated in the source

These are oral, systemic effects; the shampoo label reports no detectable plasma drug. The page gives no label dosing.

Read the original source
EMA CHMP, 25 July 2013: suspension of oral ketoconazole recommended; shampoos may continue

Regulatory record

European Medicines Agency. Ketoconazole-containing medicines, referral procedure page. CHMP recommendation of 25 July 2013.

On 25 July 2013 the EMA's CHMP recommended suspending the marketing authorizations of oral ketoconazole throughout the EU for fungal infections, concluding that the risk of liver injury outweighed the benefits; liver injury occurred early after starting recommended doses and no measure could adequately reduce the risk. The same review said topical ketoconazole formulations, including shampoos, have very low systemic absorption and may continue to be used as approved.

Participants / model
Patients treated for fungal infections in the EU
Treatment
Oral ketoconazole; topical formulations as the comparison
Follow-up
Recommendation of 25 July 2013
Study design
EMA regulatory benefit-risk decision
Funding
not stated in the source

This page reports the CHMP recommendation. Later steps in the procedure are not covered.

Read the original source
Cochrane review: 51 studies, 12 ketoconazole trials, 3,253 participants

Systematic review and meta-analysis

Okokon EO et al. Cochrane Database Syst Rev. 2015(5):CD008138. PMID 25933684.

The review included 51 studies with 9,052 participants, among them 12 ketoconazole trials (3,253 participants) against placebo or vehicle. Topical ketoconazole 2% gave a 31% lower risk of failed clearance than placebo at four weeks (RR 0.69, 95% CI 0.59 to 0.81; 8 studies; low-quality evidence), remission similar to topical steroids (RR 1.17, 95% CI 0.95 to 1.44), and fewer side effects than steroids (RR 0.56, 95% CI 0.32 to 0.96).

Participants / model
People with seborrheic dermatitis in randomized trials
Treatment
Topical ketoconazole, mainly 2%
Follow-up
Clearance assessed at four weeks in the placebo comparison
Study design
Cochrane systematic review of randomized trials
Funding
not stated in the source

This is evidence for seborrheic dermatitis, not hair loss.

Read the original source
Small comparison: ketoconazole shampoo versus minoxidil, participant number not stated

Human study

Piérard-Franchimont C et al. Dermatology. 1998;196(4):474-7. PMID 9669136.

Hair density, hair size and the proportion of anagen follicles improved almost similarly with the ketoconazole and minoxidil regimens, and casual sebum appeared lower with ketoconazole. The abstract does not give the number of participants, and the authors said clinical significance awaited a larger controlled study.

Participants / model
People with androgenic alopecia (number not stated in the abstract)
Treatment
Ketoconazole 2% shampoo compared with an unmedicated shampoo, with or without minoxidil 2%
Follow-up
not stated in the source
Study design
Original comparative clinical study
Funding
not stated in the source

Endpoints were hair density, hair size, anagen proportion and sebum. The participant count needs the full text.

Read the original source
150 men, 6 months: hair density unchanged, no unmedicated control

Randomized controlled trial

Piérard-Franchimont C et al. Int J Cosmet Sci. 2002;24(5):249-56. PMID 18498517.

Vertex hair density was unchanged. Shedding fell 17.3%, 16.5% and 10.1%; anagen percentage rose 4.9%, 7.9% and 6.8%; and mean hair shaft diameter rose 5.4% and 7.7% with ketoconazole and piroctone olamine and fell 2.2% with zinc pyrithione. Piroctone olamine performed comparably to ketoconazole.

Participants / model
150 men with androgenic alopecia-related telogen effluvium and dandruff
Treatment
Ketoconazole 1%, piroctone olamine 1% or zinc pyrithione 1% shampoo, 2 to 3 times a week
Follow-up
6 months
Study design
Randomized comparison of three anti-dandruff shampoos
Funding
not stated in the source

There was no unmedicated control. Endpoints were hair density, shedding, anagen percentage, shaft diameter and sebum.

Read the original source
Systematic review: 5 human studies (318 participants) and 2 mouse studies

Systematic review and meta-analysis

Fields JR et al. Dermatol Ther. 2020;33(1):e13202. PMID 31858672.

The review included five human studies (318 participants) and two mouse studies (40 animals). The human studies reported larger hair shaft diameter, one reported a higher pilary index, and photographic and subjective assessments improved; the authors concluded that randomized controlled trials are needed.

Participants / model
Five human studies and two mouse studies
Treatment
Topical ketoconazole, mostly shampoo
Follow-up
not stated in the source
Study design
Systematic review
Funding
not stated in the source

Endpoints were hair shaft diameter, pilary index and photographic assessment.

Read the original source
Mouse coat regrowth: 2% ketoconazole beat vehicle, n = 10

Animal study

Jiang J et al. J Dermatol. 2005;32(4):243-7. PMID 15863844.

Ketoconazole produced significantly more coat regrowth than vehicle (p < 0.01, n = 10), and repeat experiments agreed. The mechanism was unclear.

Participants / model
Male C3H/HeN mice
Treatment
Topical 2% ketoconazole in 95% ethanol, daily to clipped dorsal skin
Follow-up
3 weeks
Study design
Original animal study
Funding
not stated in the source

This is mouse coat regrowth, not human scalp hair.

Read the original source
Cell study: weak androgen receptor competition at high concentration

Cell study

Eil C. Horm Metab Res. 1992;24(8):367-70. PMID 1526623.

Ketoconazole competed for androgen receptor binding with 50% displacement at 6.4 (SE 1.8) x 10^-5 M, and the author noted this concentration is not likely to be reached in vivo, at least in plasma. Of the imidazoles tested (with clotrimazole, miconazole and fluconazole), only ketoconazole interacted with the receptor.

Participants / model
Cultured human skin fibroblasts
Treatment
In-vitro ketoconazole
Follow-up
not stated in the source
Study design
Original laboratory study
Funding
not stated in the source

This supports a weak receptor interaction at high concentration, not a measured scalp anti-androgen effect from shampoo.

Read the original source
Oral ketoconazole in young men: steep testosterone fall, nadir at 4 to 5 hours

Randomized controlled trial

Nashan D et al. Acta Endocrinol (Copenh). 1989;120(5):677-81. PMID 2499150.

The single oral ketoconazole dose caused a steep fall in serum testosterone with a nadir at 4 to 5 hours and subnormal levels for about 8 to 9 hours, with a rise in 17-hydroxyprogesterone; terbinafine had no such effect.

Participants / model
Normal young men (number not stated in the abstract)
Treatment
Single oral doses of ketoconazole 200 mg, terbinafine 500 mg or placebo on three occasions in random order
Follow-up
Single doses on three occasions
Study design
Double-blind, placebo-controlled study with random-order crossover
Funding
not stated in the source

This documented anti-androgen action comes from oral dosing. Endpoints were serum testosterone, 17-hydroxyprogesterone and LH pulses.

Read the original source
PubChem CID 47576: C26H28Cl2N4O4, 531.4 g/mol

Chemical identity record

National Center for Biotechnology Information. PubChem Compound Summary for CID 47576, ketoconazole.

Ketoconazole: PubChem CID 47576, C26H28Cl2N4O4, 531.4 g/mol, CAS 65277-42-1. The US tablet label describes the drug as the (+/-)-cis racemate. Levoketoconazole (RECORLEV) is the 2S,4R enantiomer, approved for endogenous hypercortisolemia in Cushing's syndrome and not for fungal infections, with its own hepatotoxicity and QT boxed warning. A NIZORAL-branded Hair Regrowth Treatment for Men contains minoxidil 5%, not ketoconazole.

Participants / model
Chemical identity, not a clinical population
Treatment
Defined molecule; product identity
Follow-up
Not applicable
Study design
NLM chemical record
Funding
not stated in the source

Identity record only; it says nothing about efficacy or safety. The PubChem stereo naming for this record needs a second look on the record page.

Read the original source

Why is Ketoconazole in A tier?

A fits a long-approved topical antifungal with a Cochrane review in seborrheic dermatitis and no detectable plasma drug after long-term shampooing in the label studies. The grade covers the topical labeled uses. The hair-loss data are small and mostly uncontrolled, the anti-androgen effect is documented only for oral dosing and cell culture, and the oral tablets are a separate product with a boxed warning.