Tropisetron

updated

Tropisetron is registered in Australia as an intravenous prescription antiemetic for chemotherapy-induced and postoperative nausea and vomiting, and no FDA-approved product was located on 9 October 2026. A 2024 meta-analysis supports its postoperative effect. The alpha7 cognition claim rests on short trials in about 40 medicated schizophrenia patients each and one registry-posted 12-week trial with near-identical composite scores, and no test of cognition in healthy adults was found.

5-HT3 receptor antagonist (antiemetic) with alpha7 nicotinic partial agonist activity

  • ARTG 189944 and 189943 (TROPISETRON-AFT intravenous ampoules, sponsor AFT Pharmaceuticals, ARTG start 16 November 2012) are registered prescription medicines in Australia for nausea and vomiting from cytotoxic therapy and after surgery.
  • Irish HPRA records list the originator NAVOBAN capsule and injection licences as withdrawn on 30 November 2000, and openFDA queries on 9 October 2026 returned no tropisetron application.
  • A 2024 meta-analysis of randomized trials found prophylactic tropisetron lowered postoperative nausea and vomiting (RR 0.622) and raised complete responses (RR 1.517) versus pooled control groups.
  • In healthy non-smoking men, a single oral dose of tropisetron, but not ondansetron, lowered binding of an alpha7 PET tracer, with no cognitive endpoint measured.
  • The 179-patient registry trial (NCT00435370) reported MATRICS composites of 96 (SD 16) on tropisetron and 95 (SD 15) on placebo, with no peer-reviewed report.
  • A PubMed search on 9 October 2026 for tropisetron with healthy or volunteers returned 38 records, and none measured cognition, memory, or attention in healthy people.

Where is tropisetron approved, and for what?

Tropisetron is a registered prescription medicine in Australia, as intravenous ampoules for nausea and vomiting from cytotoxic therapy and after surgery. No FDA-approved tropisetron product was located, and the originator NAVOBAN licences in Ireland were withdrawn in 2000.

In Australia, ARTG 189944 (TROPISETRON-AFT 5 mg/5 mL ampoule, sponsor AFT Pharmaceuticals, ARTG start 16 November 2012, status active) is indicated for prevention of nausea and vomiting induced by cytotoxic therapy. ARTG 189943 (2 mg/2 mL ampoule, same sponsor and start date) is indicated for treatment and prevention of postoperative nausea and vomiting in adults. Both are intravenous and Schedule 4 (prescription only). The record effective date is 14 April 2026.

The originator did not keep every market: Irish HPRA records list the NAVOBAN capsule and injection licences (Novartis Pharmaceuticals UK Ltd, PA0013/048/001 to 003, issued 23 February 1993 and 30 April 1999) as withdrawn on 30 November 2000. Only the generic Australian public summaries were read, so the originator's status in Australia and Switzerland is not established here.

On 9 October 2026, openFDA Drugs@FDA queries for tropisetron by brand or generic name, by active ingredient (TROPISETRON and TROPISETRON HYDROCHLORIDE), and for the brand NAVOBAN each returned no matching application. This supports only a dated, US-scoped statement that no FDA-approved tropisetron product was located.

Tropisetron free base is C17H20N2O2 (284.35 g/mol, CAS 89565-68-4). The hydrochloride, the salt in the Australian ampoules, is C17H21ClN2O2 (320.8 g/mol, CAS 105826-92-4), and 5.65 mg of the salt equals 5 mg of base. The former code is ICS 205-930 (SDZ-ICS-930). Clinical doses are expressed as tropisetron base, and vendor powders may be either form.

TGA ARTG: registered in Australia since 2012; NAVOBAN withdrawn in Ireland 2000

Regulatory record

Therapeutic Goods Administration, Australian Register of Therapeutic Goods (ARTG) public summary for ARTG 189944 (TROPISETRON-AFT 5 mg/5 mL ampoule) and ARTG 189943 (2 mg/2 mL ampoule), record effective date 14 April 2026; Health Products Regulatory Authority (Ireland) withdrawn-medicine records for NAVOBAN licences PA0013/048/001 to 003.

Tropisetron is a registered prescription medicine in Australia. ARTG 189944 (TROPISETRON-AFT 5 mg/5 mL ampoule, sponsor AFT Pharmaceuticals, ARTG start 16 November 2012, status active) is indicated for prevention of nausea and vomiting induced by cytotoxic therapy, and ARTG 189943 (2 mg/2 mL ampoule, same sponsor and start date) for treatment and prevention of postoperative nausea and vomiting in adults. Both are intravenous and Schedule 4 (prescription only); each 5 mg ampoule contains 5.65 mg tropisetron hydrochloride, equivalent to 5 mg tropisetron. The originator did not keep every market: Irish HPRA records list the NAVOBAN capsule and injection licences (Novartis Pharmaceuticals UK Ltd, PA0013/048/001 to 003, issued 23 February 1993 and 30 April 1999) as withdrawn on 30 November 2000.

Participants / model
Adults receiving cytotoxic therapy (5 mg ampoule); adults after surgery (2 mg ampoule)
Treatment
Tropisetron hydrochloride solution for intravenous injection, 2 mg/2 mL and 5 mg/5 mL ampoules
Follow-up
ARTG start 16 November 2012; record effective 14 April 2026
Study design
Official regulator records (TGA ARTG public summaries; HPRA withdrawn-medicine records)
Funding
not stated in the source

Only the generic ARTG public summaries were read. The originator NAVOBAN status in Australia and Switzerland is not established here, and the TGA product information was not reviewed.

Read the original source
openFDA, 9 October 2026: no tropisetron or NAVOBAN application

Regulatory record

U.S. Food and Drug Administration. openFDA Drugs@FDA queries for tropisetron by brand or generic name, by active ingredient (TROPISETRON and TROPISETRON HYDROCHLORIDE), and for the brand NAVOBAN, run on 9 October 2026.

No US approval was found. On 9 October 2026, openFDA Drugs@FDA queries for tropisetron by brand or generic name, by active ingredient (TROPISETRON and TROPISETRON HYDROCHLORIDE), and for the brand NAVOBAN each returned no matching application.

Participants / model
FDA application database, not a clinical population
Treatment
Exact name and ingredient searches
Follow-up
Search run on 9 October 2026
Study design
Dated US approval-record search
Funding
not stated in the source

This supports only the dated, US-scoped statement that no FDA-approved tropisetron product was located.

Read the original source
PubChem: tropisetron and tropisetron hydrochloride identity

Chemical identity record

National Library of Medicine. PubChem compound records CID 656665 (tropisetron) and CID 656664 (tropisetron hydrochloride).

Tropisetron free base: PubChem CID 656665, C17H20N2O2, 284.35 g/mol, CAS 89565-68-4. Tropisetron hydrochloride, the salt in the Australian ampoules: CID 656664, C17H21ClN2O2, 320.8 g/mol, CAS 105826-92-4; 5.65 mg of the salt equals 5 mg of base. Former code ICS 205-930 (SDZ-ICS-930). Clinical doses are expressed as tropisetron base, and vendor powders may be either form.

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

Identity record only. Vendor powders may be either form.

Read the original source

What did the antiemetic trials find?

A 2024 meta-analysis of randomized trials found prophylactic tropisetron in surgery under general anesthesia lowered rescue antiemetic use, postoperative nausea and vomiting, and raised complete response versus pooled control groups.

A 2024 systematic review and meta-analysis with trial sequential analysis of randomized trials of prophylactic tropisetron in surgery under general anesthesia found lower rescue antiemetic use (RR 0.718, 95% CI 0.652 to 0.790), postoperative nausea (RR 0.587, 95% CI 0.455 to 0.757), vomiting (RR 0.655, 95% CI 0.532 to 0.806), and nausea and vomiting (RR 0.622, 95% CI 0.552 to 0.700) than in pooled control groups. Complete responses were more frequent (RR 1.517, 95% CI 1.222 to 1.885).

The control groups were placebo, other antiemetics, or combinations, and the abstract does not state the number of trials or patients. This is the evidence for the registered use, not for the cognition claim.

2024 meta-analysis: postoperative nausea and vomiting RR 0.622 with tropisetron

Systematic review and meta-analysis

Kim IJ et al. J Pers Med. 2024;14(8). PMID 39201989.

Prophylactic tropisetron gave lower rescue antiemetic use (RR 0.718, 95% CI 0.652 to 0.790), postoperative nausea (RR 0.587, 95% CI 0.455 to 0.757), vomiting (RR 0.655, 95% CI 0.532 to 0.806), and nausea and vomiting (RR 0.622, 95% CI 0.552 to 0.700) than pooled control groups, and more complete responses (RR 1.517, 95% CI 1.222 to 1.885). The abstract does not state the number of trials or patients.

Participants / model
Patients having surgery under general anesthesia in randomized trials
Treatment
Perioperative tropisetron versus placebo, other antiemetics, or combinations
Follow-up
not stated in the source
Study design
Systematic review and meta-analysis with trial sequential analysis
Funding
not stated in the source

The control groups pooled placebo, other antiemetics and combinations. The abstract does not state the number of trials or patients.

Read the original source

What did the schizophrenia studies show for cognition?

Short trials in about 40 medicated schizophrenia patients each found cognitive and gating gains, while the largest trial, posted only in a registry, had near-identical composite scores. Symptom-scale meta-analysis is not a cognitive test.

In an 8-week randomized double-blind trial in 40 patients with chronic schizophrenia taking risperidone 2 to 6 mg/day, adjunctive tropisetron 10 mg/day (n = 20) versus placebo (n = 20) improved P50 auditory gating in non-smokers and the CANTAB rapid visual information processing (sustained attention) score. PANSS scores did not change. 33 patients completed. Quality of life improved in the whole sample but not in non-smokers.

In 40 non-smoking patients with schizophrenia, P50 ratios above 0.5, and stable risperidone 3 to 6 mg/day, 10 days of oral tropisetron at 5, 10, or 20 mg/day (10 per arm) versus placebo improved overall RBANS cognitive scores at all three doses, and P50 gains correlated with cognitive gains. Two patients on 20 mg/day dropped out with adverse effects. A separate 1-day trial of the same design and size by the same group (PMID 32349117) reported higher RBANS total scores at 5 and 20 mg and higher immediate memory at 10 mg than placebo.

The largest tropisetron cognition trial in the records has registry-posted results but no peer-reviewed report: 179 patients randomized to tropisetron 10 mg/day (n = 90) or placebo (n = 89), both with risperidone 6 mg/day, for 12 weeks (Baylor College of Medicine; Chinese patients described as first-episode and drug-naive; 68 and 69 completed). The MATRICS composite at 12 weeks was 96 (SD 16) on tropisetron and 95 (SD 15) on placebo, and the registry reports an ANCOVA p below 0.05. The means are near identical, so the full analysis would be needed before drawing a conclusion. A PubMed search on 9 October 2026 for tropisetron AND (MATRICS OR MCCB OR 12 weeks OR 12-week) AND schizophrenia returned 0 records.

A meta-analysis of six add-on trials (n = 311; three tropisetron, two ondansetron, one granisetron) found that 5-HT3 antagonists improved PANSS total (SMD -1.03, 95% CI -1.70 to -0.36; 5 studies, n = 261), negative (SMD -1.10), and general (SMD -0.70) scores, but not positive scores, with high heterogeneity (I2 73 to 84%). These are symptom scales, not cognitive tests. A 2026 Bayesian network meta-analysis of 30 trials (3128 participants; PMID 41321045) also found tropisetron 5 mg effective on PANSS total.

Schizophrenia add-on trial: 40 patients, 8 weeks, P50 gating and sustained attention

Randomized controlled trial

Shiina A et al. Ann Gen Psychiatry. 2010;9:27. PMID 20573264.

Adjunctive tropisetron 10 mg/day (n = 20) versus placebo (n = 20) improved P50 auditory gating in non-smokers and the CANTAB rapid visual information processing (sustained attention) score. PANSS scores did not change. 33 patients completed. Quality of life improved in the whole sample but not in non-smokers.

Participants / model
40 adults with chronic schizophrenia taking risperidone 2 to 6 mg/day
Treatment
Oral tropisetron 10 mg/day added to risperidone, or placebo
Follow-up
8 weeks
Study design
Randomized double-blind placebo-controlled trial; P50 gating, CANTAB, PANSS, Quality of Life Scale
Funding
not stated in the source

A small trial in medicated patients with schizophrenia. It does not describe healthy adults.

Read the original source
Schizophrenia dose trials: 40 non-smoking patients each, 10 days and 1 day, RBANS gains

Randomized controlled trial

Zhang XY et al. Am J Psychiatry. 2012;169(9):974-81. PMID 22952075.

Ten days of oral tropisetron at 5, 10, or 20 mg/day (10 per arm) versus placebo improved overall RBANS cognitive scores at all three doses, and P50 gains correlated with cognitive gains. Two patients on 20 mg/day dropped out with adverse effects. A separate 1-day trial of the same design and size by the same group (PMID 32349117) reported higher RBANS total scores at 5 and 20 mg and higher immediate memory at 10 mg than placebo.

Participants / model
40 non-smoking adults with schizophrenia, P50 ratios above 0.5, on stable risperidone 3 to 6 mg/day (each trial)
Treatment
Oral tropisetron 5, 10, or 20 mg/day added to risperidone, or placebo
Follow-up
10 days (and 1 day in the companion trial)
Study design
Randomized placebo-controlled trials; RBANS cognitive battery, P50 gating, dropouts
Funding
not stated in the source

Short trials in medicated, non-smoking patients with schizophrenia, with 10 patients per arm.

Read the original source
Registry NCT00435370: 179 patients, 12 weeks, MATRICS 96 versus 95, no peer-reviewed report

Trial registry record

ClinicalTrials.gov record NCT00435370 (Baylor College of Medicine), results posted in the registry and read through the ClinicalTrials.gov API v2.

The registry posts results for 179 patients randomized to tropisetron 10 mg/day (n = 90) or placebo (n = 89), both with risperidone 6 mg/day, for 12 weeks (Chinese patients described as first-episode and drug-naive; 68 and 69 completed). The MATRICS composite at 12 weeks was 96 (SD 16) on tropisetron and 95 (SD 15) on placebo, and the registry reports an ANCOVA p below 0.05. No serious adverse events occurred in either arm (0 of 90, 0 of 89). A PubMed search on 9 October 2026 for tropisetron AND (MATRICS OR MCCB OR "12 weeks" OR "12-week") AND schizophrenia returned 0 records.

Participants / model
179 Chinese patients with schizophrenia
Treatment
Oral tropisetron 10 mg/day or placebo, each with risperidone 6 mg/day
Follow-up
12 weeks
Study design
Randomized trial with registry-posted results and no peer-reviewed report
Funding
not stated in the source

The largest tropisetron cognition trial in these records has registry-posted results only. The group means are near identical while the registry reports a p below 0.05, so the full analysis is needed before any conclusion is drawn.

Read the original source
Add-on meta-analysis: six trials, 311 patients, PANSS improved, constipation more common

Systematic review and meta-analysis

Kishi T et al. Neuromolecular Med. 2014;16(1):61-9. PMID 23896722.

Across six add-on trials (n = 311; three tropisetron, two ondansetron, one granisetron), 5-HT3 antagonists improved PANSS total (SMD -1.03, 95% CI -1.70 to -0.36; 5 studies, n = 261), negative (SMD -1.10), and general (SMD -0.70) scores, but not positive scores, with high heterogeneity (I2 73 to 84%). Constipation was more common than with placebo (RR 2.05, 95% CI 1.07 to 3.91; NNH 11), and dropouts did not differ. A 2026 Bayesian network meta-analysis of 30 trials (3128 participants; PMID 41321045) also found tropisetron 5 mg effective on PANSS total.

Participants / model
Adults with schizophrenia in add-on randomized trials
Treatment
Oral 5-HT3 antagonists added to antipsychotics
Follow-up
not stated in the source
Study design
Meta-analysis of six randomized add-on trials
Funding
not stated in the source

These are symptom scales, not cognitive tests, and the trials pooled three different 5-HT3 antagonists.

Read the original source

Does tropisetron enhance cognition in healthy adults or avoid nicotine's cardiovascular profile?

No test of cognition in healthy adults was found, and no study compared tropisetron's cardiovascular effects with nicotine's. The cognition data come from medicated schizophrenia patients.

Sellers market tropisetron as a nicotinic enhancer for cognition through alpha7 nicotinic activation, with anti-inflammatory support and schizophrenia cognition research, and without nicotine's cardiovascular profile. Tropisetron does act at alpha7 receptors, but that is a receptor finding and not a cognitive outcome in healthy people.

A PubMed search on 9 October 2026 for tropisetron AND (healthy OR volunteers) returned 38 records. By title, none measured cognition, memory, or attention in healthy people; they covered pharmacokinetics, gut motility and secretion, experimental pain and itch, forearm blood flow, sleep EEG and nocturnal hormones in 12 healthy men, one PET receptor-occupancy study, and reviews. Cognitive enhancement in healthy people has no trial behind it in these records.

A PubMed search on 9 October 2026 for tropisetron AND nicotine AND (cardiovascular OR blood pressure OR heart rate OR hemodynamic) returned 1 record, a goat carotid-body study. The only human electrocardiographic study found was single-arm: in 55 cancer patients given 5 mg intravenously, heart rate fell at 30 minutes while P-wave duration, corrected QT, and their dispersions did not change significantly. The framing of tropisetron as lacking nicotine's cardiovascular profile is untested.

PubMed search, 9 October 2026: 38 records, none on cognition in healthy people

PubMed search record

PubMed search run on 9 October 2026: tropisetron AND (healthy OR volunteers). 38 records returned.

No test of cognition in healthy adults was found. The search returned 38 records. By title, none measured cognition, memory, or attention in healthy people; they covered pharmacokinetics, gut motility and secretion, experimental pain and itch, forearm blood flow, sleep EEG and nocturnal hormones in 12 healthy men (PMID 7840861), one PET receptor-occupancy study, and reviews. Cognitive enhancement in healthy people has no trial behind it in these records.

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

A search result shows what PubMed returned on that date. It is not proof that no unindexed study exists. The records were screened by title.

Read the original source
PubMed search, 9 October 2026: 1 record, no tropisetron versus nicotine comparison

PubMed search record

PubMed search run on 9 October 2026: tropisetron AND nicotine AND (cardiovascular OR blood pressure OR heart rate OR hemodynamic). 1 record returned.

No study compared tropisetron's cardiovascular effects with nicotine's. The search returned 1 record, a goat carotid-body study. The only human electrocardiographic study found was single-arm: in 55 cancer patients given 5 mg intravenously, heart rate fell at 30 minutes while P-wave duration, corrected QT, and their dispersions did not change significantly (PMID 18239945). The framing of tropisetron as lacking nicotine's cardiovascular profile is untested.

Participants / model
Records returned; 55 cancer patients in the ECG study
Treatment
Not applicable; 5 mg intravenous bolus in the ECG study
Follow-up
Search run on 9 October 2026
Study design
Literature search
Funding
not stated in the source

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

Read the original source

What does the one surgical trial show about inflammation?

In 75 patients having heart valve replacement, tropisetron lowered postoperative rises in troponin I, CK-MB, TNF-alpha and LDH and raised IL-10. It was the only randomized trial with inflammatory-marker endpoints in patients among the records reviewed.

In 75 patients having heart valve replacement with cardioplegic arrest, tropisetron 10 mg in 10 mL given right after anesthesia induction, versus 10 mL saline, reduced postoperative rises in cardiac troponin I (12 and 24 h), CK-MB (4, 12, and 24 h), TNF-alpha (4 and 12 h), and LDH (24 h), and raised IL-10 at 12 h. The route is not stated in the abstract.

Other anti-inflammatory evidence is in cultured human monocytes (PMID 22664143) and rodent models, and other non-nausea human trials measured pain, not inflammation (for example, a 418-patient fibromyalgia trial, PMID 11708570). A registered pilot of tropisetron for postoperative cognitive dysfunction after cardiac surgery (NCT04195204) has no results and supplies no evidence.

Cardiac surgery trial: 75 patients, lower troponin, CK-MB, TNF-alpha and LDH

Randomized controlled trial

Yu D et al. Front Med (Lausanne). 2022;9:690272. PMID 35425785.

In 75 patients having heart valve replacement with cardioplegic arrest, tropisetron 10 mg in 10 mL given right after anesthesia induction, versus 10 mL saline, reduced postoperative rises in cardiac troponin I (12 and 24 h), CK-MB (4, 12, and 24 h), TNF-alpha (4 and 12 h), and LDH (24 h), and raised IL-10 at 12 h.

Participants / model
75 adults having elective heart valve replacement
Treatment
Single dose of tropisetron 10 mg after anesthesia induction, or saline (route not stated in the abstract)
Follow-up
Postoperative markers to 24 hours
Study design
Randomized trial of myocardial injury markers and cytokines
Funding
not stated in the source

The only randomized trial with inflammatory-marker endpoints in patients among the records reviewed. Other anti-inflammatory evidence is in cultured human monocytes (PMID 22664143) and rodent models, and other non-nausea human trials measured pain, not inflammation (for example, a 418-patient fibromyalgia trial, PMID 11708570).

Read the original source

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

Tropisetron is a 5-HT3 receptor antagonist that is also a potent, selective partial agonist at alpha7 nicotinic receptors. In healthy volunteers its half-life was 5.7 hours orally, and exposure rose with poor-metabolizer CYP2D6 alleles.

Receptor pharmacology identified tropisetron, a 5-HT3 receptor antagonist, as a potent and selective partial agonist at alpha7 nicotinic receptors. Two other 5-HT3 antagonists, ondansetron and LY-278,584, lacked high alpha7 affinity, so the nicotinic action is specific to tropisetron among the drugs tested. This is in vitro evidence, not a cognitive outcome.

In healthy non-smoking men, a single oral dose of tropisetron, but not ondansetron, lowered the total distribution volume of the alpha7 PET tracer [11C]CHIBA-1001, consistent with tropisetron binding alpha7 receptors in the living human brain. The abstract does not state the dose or the number of participants, and no cognitive endpoint was measured.

In Xenopus oocytes expressing human receptors, tropisetron was a partial agonist at alpha7 (EC50 about 2.4 micromolar) and alpha7beta2 (about 1.5 micromolar) receptors, and low concentrations (10 and 30 nM) enhanced acetylcholine-evoked currents. Tropisetron (0.1 to 10 mg/kg) improved novel object recognition in young and aged rats, and in aged rhesus monkeys (0.03 to 1 mg/kg) raised long-delay matching accuracy 17% from baseline; combining doses of donepezil and tropisetron that were each ineffective alone gave a 24% change. These are animal and cell findings, not human cognition, and the route is not given in the abstract.

In 18 healthy volunteers, 5 mg oral tropisetron gave a mean Cmax of 3.46 ng/mL at 2.6 h and a half-life of 5.7 h; after 2 mg intravenously the half-life was 5.6 h, volume 678 L, and clearance 1800 mL/min. Oral bioavailability averaged 0.60 (range 0.27 to 0.99) and fell as CYP2D6 activity rose. In 13 healthy Korean subjects given 5 mg, mean AUC was 1.9-fold higher in carriers of one and 6.8-fold higher in carriers of two poor-metabolizer-associated CYP2D6 alleles than in wild-type carriers.

In vitro receptor assays: tropisetron is an alpha7 partial agonist; ondansetron is not

Cell study

Macor JE et al. Bioorg Med Chem Lett. 2001;11(3):319-21. PMID 11212100.

Receptor pharmacology identified tropisetron, a 5-HT3 receptor antagonist, as a potent and selective partial agonist at alpha7 nicotinic receptors. Two other 5-HT3 antagonists, ondansetron and LY-278,584, lacked high alpha7 affinity, so the nicotinic action is specific to tropisetron among the drugs tested.

Participants / model
In vitro receptor assays
Treatment
Not applicable
Follow-up
not stated in the source
Study design
Original mechanistic study of receptor affinity and partial agonism
Funding
not stated in the source

This is in vitro evidence, not a cognitive outcome.

Read the original source
PET: tropisetron, not ondansetron, lowered alpha7 tracer binding in healthy men

Human study

Ishikawa M et al. Clin Psychopharmacol Neurosci. 2011;9(3):111-6. PMID 23430308.

A single oral dose of tropisetron, but not ondansetron, lowered the total distribution volume of the alpha7 PET tracer [11C]CHIBA-1001, consistent with tropisetron binding alpha7 receptors in the living human brain. The abstract does not state the dose or the number of participants, and no cognitive endpoint was measured.

Participants / model
Healthy non-smoking men (number not stated in the abstract)
Treatment
Single oral dose of tropisetron or ondansetron (dose not stated in the abstract)
Follow-up
Single dose
Study design
Human PET receptor-occupancy study
Funding
not stated in the source

A receptor-occupancy result with no cognitive endpoint.

Read the original source
Preclinical: oocytes, rats and aged rhesus monkeys, not human cognition

Animal study

Callahan PM et al. Neuropharmacology. 2017;117:422-433. PMID 28259598.

In Xenopus oocytes expressing human receptors, tropisetron was a partial agonist at alpha7 (EC50 about 2.4 micromolar) and alpha7beta2 (about 1.5 micromolar) receptors, and low concentrations (10 and 30 nM) enhanced acetylcholine-evoked currents. Tropisetron (0.1 to 10 mg/kg) improved novel object recognition in young and aged rats, and in aged rhesus monkeys (0.03 to 1 mg/kg) raised long-delay matching accuracy 17% from baseline; combining doses of donepezil and tropisetron that were each ineffective alone gave a 24% change.

Participants / model
Xenopus oocytes with human receptors; young Sprague-Dawley rats; aged Fischer rats; aged rhesus monkeys
Treatment
Doses as stated; route not given in the abstract
Follow-up
not stated in the source
Study design
Original preclinical study of receptor currents, novel object recognition and delayed match-to-sample accuracy
Funding
not stated in the source

These are animal and cell findings, not human cognition. The route of administration is not given in the abstract.

Read the original source
PK in 18 healthy volunteers: half-life 5.7 hours, bioavailability 0.60

Human study

Kees F et al. Br J Clin Pharmacol. 2001;52(6):705-7. PMID 11736884.

In 18 healthy volunteers, 5 mg oral tropisetron gave a mean Cmax of 3.46 ng/mL at 2.6 h and a half-life of 5.7 h; after 2 mg intravenously the half-life was 5.6 h, volume 678 L, and clearance 1800 mL/min. Oral bioavailability averaged 0.60 (range 0.27 to 0.99) and fell as CYP2D6 activity rose. In 13 healthy Korean subjects given 5 mg, mean AUC was 1.9-fold higher in carriers of one and 6.8-fold higher in carriers of two poor-metabolizer-associated CYP2D6 alleles than in wild-type carriers (PMID 12728290).

Participants / model
18 healthy volunteers; 13 healthy Korean subjects
Treatment
Single 5 mg oral capsule; single 2 mg intravenous bolus
Follow-up
Single doses
Study design
Clinical pharmacokinetic studies with CYP2D6 genotype comparison
Funding
not stated in the source

Single-dose studies in healthy volunteers. Exposure varies with CYP2D6 genotype.

Read the original source

What risks do the studies report?

In the trials found, two patients on the highest dose dropped out with adverse effects, no serious adverse events occurred in the 179-patient registry trial, and constipation was more common than placebo. Full label warnings were not reviewed, so label-level risk is not covered here.

In the 10-day schizophrenia trial, two patients on 20 mg/day dropped out with adverse effects. In the 179-patient registry trial, no serious adverse events occurred in either arm (0 of 90, 0 of 89). In the meta-analysis of add-on trials, constipation was more common than with placebo (RR 2.05, 95% CI 1.07 to 3.91; NNH 11), and dropouts did not differ.

In 55 cancer patients given 5 mg intravenously in a single-arm study, heart rate fell at 30 minutes while P-wave duration, corrected QT, and their dispersions did not change significantly. No study compared tropisetron's cardiovascular effects with nicotine's.

Exposure differs by genotype: mean AUC was 1.9-fold higher in carriers of one and 6.8-fold higher in carriers of two poor-metabolizer-associated CYP2D6 alleles than in wild-type carriers, in 13 healthy Korean subjects.

The Australian product information and consumer information, with full warnings, any QT or cardiac language, and adverse-event frequencies, were not reviewed. Safety statements here therefore come from the trials above, not from a label.

Schizophrenia dose trials: 40 non-smoking patients each, 10 days and 1 day, RBANS gains

Randomized controlled trial

Zhang XY et al. Am J Psychiatry. 2012;169(9):974-81. PMID 22952075.

Ten days of oral tropisetron at 5, 10, or 20 mg/day (10 per arm) versus placebo improved overall RBANS cognitive scores at all three doses, and P50 gains correlated with cognitive gains. Two patients on 20 mg/day dropped out with adverse effects. A separate 1-day trial of the same design and size by the same group (PMID 32349117) reported higher RBANS total scores at 5 and 20 mg and higher immediate memory at 10 mg than placebo.

Participants / model
40 non-smoking adults with schizophrenia, P50 ratios above 0.5, on stable risperidone 3 to 6 mg/day (each trial)
Treatment
Oral tropisetron 5, 10, or 20 mg/day added to risperidone, or placebo
Follow-up
10 days (and 1 day in the companion trial)
Study design
Randomized placebo-controlled trials; RBANS cognitive battery, P50 gating, dropouts
Funding
not stated in the source

Short trials in medicated, non-smoking patients with schizophrenia, with 10 patients per arm.

Read the original source
Registry NCT00435370: 179 patients, 12 weeks, MATRICS 96 versus 95, no peer-reviewed report

Trial registry record

ClinicalTrials.gov record NCT00435370 (Baylor College of Medicine), results posted in the registry and read through the ClinicalTrials.gov API v2.

The registry posts results for 179 patients randomized to tropisetron 10 mg/day (n = 90) or placebo (n = 89), both with risperidone 6 mg/day, for 12 weeks (Chinese patients described as first-episode and drug-naive; 68 and 69 completed). The MATRICS composite at 12 weeks was 96 (SD 16) on tropisetron and 95 (SD 15) on placebo, and the registry reports an ANCOVA p below 0.05. No serious adverse events occurred in either arm (0 of 90, 0 of 89). A PubMed search on 9 October 2026 for tropisetron AND (MATRICS OR MCCB OR "12 weeks" OR "12-week") AND schizophrenia returned 0 records.

Participants / model
179 Chinese patients with schizophrenia
Treatment
Oral tropisetron 10 mg/day or placebo, each with risperidone 6 mg/day
Follow-up
12 weeks
Study design
Randomized trial with registry-posted results and no peer-reviewed report
Funding
not stated in the source

The largest tropisetron cognition trial in these records has registry-posted results only. The group means are near identical while the registry reports a p below 0.05, so the full analysis is needed before any conclusion is drawn.

Read the original source
Add-on meta-analysis: six trials, 311 patients, PANSS improved, constipation more common

Systematic review and meta-analysis

Kishi T et al. Neuromolecular Med. 2014;16(1):61-9. PMID 23896722.

Across six add-on trials (n = 311; three tropisetron, two ondansetron, one granisetron), 5-HT3 antagonists improved PANSS total (SMD -1.03, 95% CI -1.70 to -0.36; 5 studies, n = 261), negative (SMD -1.10), and general (SMD -0.70) scores, but not positive scores, with high heterogeneity (I2 73 to 84%). Constipation was more common than with placebo (RR 2.05, 95% CI 1.07 to 3.91; NNH 11), and dropouts did not differ. A 2026 Bayesian network meta-analysis of 30 trials (3128 participants; PMID 41321045) also found tropisetron 5 mg effective on PANSS total.

Participants / model
Adults with schizophrenia in add-on randomized trials
Treatment
Oral 5-HT3 antagonists added to antipsychotics
Follow-up
not stated in the source
Study design
Meta-analysis of six randomized add-on trials
Funding
not stated in the source

These are symptom scales, not cognitive tests, and the trials pooled three different 5-HT3 antagonists.

Read the original source
PubMed search, 9 October 2026: 1 record, no tropisetron versus nicotine comparison

PubMed search record

PubMed search run on 9 October 2026: tropisetron AND nicotine AND (cardiovascular OR blood pressure OR heart rate OR hemodynamic). 1 record returned.

No study compared tropisetron's cardiovascular effects with nicotine's. The search returned 1 record, a goat carotid-body study. The only human electrocardiographic study found was single-arm: in 55 cancer patients given 5 mg intravenously, heart rate fell at 30 minutes while P-wave duration, corrected QT, and their dispersions did not change significantly (PMID 18239945). The framing of tropisetron as lacking nicotine's cardiovascular profile is untested.

Participants / model
Records returned; 55 cancer patients in the ECG study
Treatment
Not applicable; 5 mg intravenous bolus in the ECG study
Follow-up
Search run on 9 October 2026
Study design
Literature search
Funding
not stated in the source

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

Read the original source
PK in 18 healthy volunteers: half-life 5.7 hours, bioavailability 0.60

Human study

Kees F et al. Br J Clin Pharmacol. 2001;52(6):705-7. PMID 11736884.

In 18 healthy volunteers, 5 mg oral tropisetron gave a mean Cmax of 3.46 ng/mL at 2.6 h and a half-life of 5.7 h; after 2 mg intravenously the half-life was 5.6 h, volume 678 L, and clearance 1800 mL/min. Oral bioavailability averaged 0.60 (range 0.27 to 0.99) and fell as CYP2D6 activity rose. In 13 healthy Korean subjects given 5 mg, mean AUC was 1.9-fold higher in carriers of one and 6.8-fold higher in carriers of two poor-metabolizer-associated CYP2D6 alleles than in wild-type carriers (PMID 12728290).

Participants / model
18 healthy volunteers; 13 healthy Korean subjects
Treatment
Single 5 mg oral capsule; single 2 mg intravenous bolus
Follow-up
Single doses
Study design
Clinical pharmacokinetic studies with CYP2D6 genotype comparison
Funding
not stated in the source

Single-dose studies in healthy volunteers. Exposure varies with CYP2D6 genotype.

Read the original source

Why does tropisetron sit in A tier?

Current Australian registration for chemotherapy-induced and postoperative nausea and vomiting and a 2024 meta-analysis support the A as a narrow, regional use. The cognition, anti-inflammatory and nicotine-profile claims each rest on thin or no human data.

Tropisetron is an established antiemetic outside the US: Australia currently registers generic intravenous tropisetron for chemotherapy-induced and postoperative nausea and vomiting, and a 2024 meta-analysis supports its postoperative efficacy. No FDA-approved product was located, and the originator licences were withdrawn in Ireland in 2000, so this is strong data for a narrow, regional use.

The supplier claim stays a separate verdict. Tropisetron does bind alpha7 receptors in the human brain, but the cognition evidence is short trials in about 40 medicated schizophrenia patients each plus one registry-posted 12-week trial with near-identical composite scores. There is no healthy-adult cognition trial, the anti-inflammatory evidence in people is one surgical biomarker trial, and no study has compared its cardiovascular effects with nicotine's.

TGA ARTG: registered in Australia since 2012; NAVOBAN withdrawn in Ireland 2000

Regulatory record

Therapeutic Goods Administration, Australian Register of Therapeutic Goods (ARTG) public summary for ARTG 189944 (TROPISETRON-AFT 5 mg/5 mL ampoule) and ARTG 189943 (2 mg/2 mL ampoule), record effective date 14 April 2026; Health Products Regulatory Authority (Ireland) withdrawn-medicine records for NAVOBAN licences PA0013/048/001 to 003.

Tropisetron is a registered prescription medicine in Australia. ARTG 189944 (TROPISETRON-AFT 5 mg/5 mL ampoule, sponsor AFT Pharmaceuticals, ARTG start 16 November 2012, status active) is indicated for prevention of nausea and vomiting induced by cytotoxic therapy, and ARTG 189943 (2 mg/2 mL ampoule, same sponsor and start date) for treatment and prevention of postoperative nausea and vomiting in adults. Both are intravenous and Schedule 4 (prescription only); each 5 mg ampoule contains 5.65 mg tropisetron hydrochloride, equivalent to 5 mg tropisetron. The originator did not keep every market: Irish HPRA records list the NAVOBAN capsule and injection licences (Novartis Pharmaceuticals UK Ltd, PA0013/048/001 to 003, issued 23 February 1993 and 30 April 1999) as withdrawn on 30 November 2000.

Participants / model
Adults receiving cytotoxic therapy (5 mg ampoule); adults after surgery (2 mg ampoule)
Treatment
Tropisetron hydrochloride solution for intravenous injection, 2 mg/2 mL and 5 mg/5 mL ampoules
Follow-up
ARTG start 16 November 2012; record effective 14 April 2026
Study design
Official regulator records (TGA ARTG public summaries; HPRA withdrawn-medicine records)
Funding
not stated in the source

Only the generic ARTG public summaries were read. The originator NAVOBAN status in Australia and Switzerland is not established here, and the TGA product information was not reviewed.

Read the original source
2024 meta-analysis: postoperative nausea and vomiting RR 0.622 with tropisetron

Systematic review and meta-analysis

Kim IJ et al. J Pers Med. 2024;14(8). PMID 39201989.

Prophylactic tropisetron gave lower rescue antiemetic use (RR 0.718, 95% CI 0.652 to 0.790), postoperative nausea (RR 0.587, 95% CI 0.455 to 0.757), vomiting (RR 0.655, 95% CI 0.532 to 0.806), and nausea and vomiting (RR 0.622, 95% CI 0.552 to 0.700) than pooled control groups, and more complete responses (RR 1.517, 95% CI 1.222 to 1.885). The abstract does not state the number of trials or patients.

Participants / model
Patients having surgery under general anesthesia in randomized trials
Treatment
Perioperative tropisetron versus placebo, other antiemetics, or combinations
Follow-up
not stated in the source
Study design
Systematic review and meta-analysis with trial sequential analysis
Funding
not stated in the source

The control groups pooled placebo, other antiemetics and combinations. The abstract does not state the number of trials or patients.

Read the original source
openFDA, 9 October 2026: no tropisetron or NAVOBAN application

Regulatory record

U.S. Food and Drug Administration. openFDA Drugs@FDA queries for tropisetron by brand or generic name, by active ingredient (TROPISETRON and TROPISETRON HYDROCHLORIDE), and for the brand NAVOBAN, run on 9 October 2026.

No US approval was found. On 9 October 2026, openFDA Drugs@FDA queries for tropisetron by brand or generic name, by active ingredient (TROPISETRON and TROPISETRON HYDROCHLORIDE), and for the brand NAVOBAN each returned no matching application.

Participants / model
FDA application database, not a clinical population
Treatment
Exact name and ingredient searches
Follow-up
Search run on 9 October 2026
Study design
Dated US approval-record search
Funding
not stated in the source

This supports only the dated, US-scoped statement that no FDA-approved tropisetron product was located.

Read the original source
PubMed search, 9 October 2026: 38 records, none on cognition in healthy people

PubMed search record

PubMed search run on 9 October 2026: tropisetron AND (healthy OR volunteers). 38 records returned.

No test of cognition in healthy adults was found. The search returned 38 records. By title, none measured cognition, memory, or attention in healthy people; they covered pharmacokinetics, gut motility and secretion, experimental pain and itch, forearm blood flow, sleep EEG and nocturnal hormones in 12 healthy men (PMID 7840861), one PET receptor-occupancy study, and reviews. Cognitive enhancement in healthy people has no trial behind it in these records.

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

A search result shows what PubMed returned on that date. It is not proof that no unindexed study exists. The records were screened by title.

Read the original source
Registry NCT00435370: 179 patients, 12 weeks, MATRICS 96 versus 95, no peer-reviewed report

Trial registry record

ClinicalTrials.gov record NCT00435370 (Baylor College of Medicine), results posted in the registry and read through the ClinicalTrials.gov API v2.

The registry posts results for 179 patients randomized to tropisetron 10 mg/day (n = 90) or placebo (n = 89), both with risperidone 6 mg/day, for 12 weeks (Chinese patients described as first-episode and drug-naive; 68 and 69 completed). The MATRICS composite at 12 weeks was 96 (SD 16) on tropisetron and 95 (SD 15) on placebo, and the registry reports an ANCOVA p below 0.05. No serious adverse events occurred in either arm (0 of 90, 0 of 89). A PubMed search on 9 October 2026 for tropisetron AND (MATRICS OR MCCB OR "12 weeks" OR "12-week") AND schizophrenia returned 0 records.

Participants / model
179 Chinese patients with schizophrenia
Treatment
Oral tropisetron 10 mg/day or placebo, each with risperidone 6 mg/day
Follow-up
12 weeks
Study design
Randomized trial with registry-posted results and no peer-reviewed report
Funding
not stated in the source

The largest tropisetron cognition trial in these records has registry-posted results only. The group means are near identical while the registry reports a p below 0.05, so the full analysis is needed before any conclusion is drawn.

Read the original source
Cardiac surgery trial: 75 patients, lower troponin, CK-MB, TNF-alpha and LDH

Randomized controlled trial

Yu D et al. Front Med (Lausanne). 2022;9:690272. PMID 35425785.

In 75 patients having heart valve replacement with cardioplegic arrest, tropisetron 10 mg in 10 mL given right after anesthesia induction, versus 10 mL saline, reduced postoperative rises in cardiac troponin I (12 and 24 h), CK-MB (4, 12, and 24 h), TNF-alpha (4 and 12 h), and LDH (24 h), and raised IL-10 at 12 h.

Participants / model
75 adults having elective heart valve replacement
Treatment
Single dose of tropisetron 10 mg after anesthesia induction, or saline (route not stated in the abstract)
Follow-up
Postoperative markers to 24 hours
Study design
Randomized trial of myocardial injury markers and cytokines
Funding
not stated in the source

The only randomized trial with inflammatory-marker endpoints in patients among the records reviewed. Other anti-inflammatory evidence is in cultured human monocytes (PMID 22664143) and rodent models, and other non-nausea human trials measured pain, not inflammation (for example, a 418-patient fibromyalgia trial, PMID 11708570).

Read the original source
PubMed search, 9 October 2026: 1 record, no tropisetron versus nicotine comparison

PubMed search record

PubMed search run on 9 October 2026: tropisetron AND nicotine AND (cardiovascular OR blood pressure OR heart rate OR hemodynamic). 1 record returned.

No study compared tropisetron's cardiovascular effects with nicotine's. The search returned 1 record, a goat carotid-body study. The only human electrocardiographic study found was single-arm: in 55 cancer patients given 5 mg intravenously, heart rate fell at 30 minutes while P-wave duration, corrected QT, and their dispersions did not change significantly (PMID 18239945). The framing of tropisetron as lacking nicotine's cardiovascular profile is untested.

Participants / model
Records returned; 55 cancer patients in the ECG study
Treatment
Not applicable; 5 mg intravenous bolus in the ECG study
Follow-up
Search run on 9 October 2026
Study design
Literature search
Funding
not stated in the source

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

Read the original source

Studies and sources

TGA ARTG: registered in Australia since 2012; NAVOBAN withdrawn in Ireland 2000

Regulatory record

Therapeutic Goods Administration, Australian Register of Therapeutic Goods (ARTG) public summary for ARTG 189944 (TROPISETRON-AFT 5 mg/5 mL ampoule) and ARTG 189943 (2 mg/2 mL ampoule), record effective date 14 April 2026; Health Products Regulatory Authority (Ireland) withdrawn-medicine records for NAVOBAN licences PA0013/048/001 to 003.

Tropisetron is a registered prescription medicine in Australia. ARTG 189944 (TROPISETRON-AFT 5 mg/5 mL ampoule, sponsor AFT Pharmaceuticals, ARTG start 16 November 2012, status active) is indicated for prevention of nausea and vomiting induced by cytotoxic therapy, and ARTG 189943 (2 mg/2 mL ampoule, same sponsor and start date) for treatment and prevention of postoperative nausea and vomiting in adults. Both are intravenous and Schedule 4 (prescription only); each 5 mg ampoule contains 5.65 mg tropisetron hydrochloride, equivalent to 5 mg tropisetron. The originator did not keep every market: Irish HPRA records list the NAVOBAN capsule and injection licences (Novartis Pharmaceuticals UK Ltd, PA0013/048/001 to 003, issued 23 February 1993 and 30 April 1999) as withdrawn on 30 November 2000.

Participants / model
Adults receiving cytotoxic therapy (5 mg ampoule); adults after surgery (2 mg ampoule)
Treatment
Tropisetron hydrochloride solution for intravenous injection, 2 mg/2 mL and 5 mg/5 mL ampoules
Follow-up
ARTG start 16 November 2012; record effective 14 April 2026
Study design
Official regulator records (TGA ARTG public summaries; HPRA withdrawn-medicine records)
Funding
not stated in the source

Only the generic ARTG public summaries were read. The originator NAVOBAN status in Australia and Switzerland is not established here, and the TGA product information was not reviewed.

Read the original source
2024 meta-analysis: postoperative nausea and vomiting RR 0.622 with tropisetron

Systematic review and meta-analysis

Kim IJ et al. J Pers Med. 2024;14(8). PMID 39201989.

Prophylactic tropisetron gave lower rescue antiemetic use (RR 0.718, 95% CI 0.652 to 0.790), postoperative nausea (RR 0.587, 95% CI 0.455 to 0.757), vomiting (RR 0.655, 95% CI 0.532 to 0.806), and nausea and vomiting (RR 0.622, 95% CI 0.552 to 0.700) than pooled control groups, and more complete responses (RR 1.517, 95% CI 1.222 to 1.885). The abstract does not state the number of trials or patients.

Participants / model
Patients having surgery under general anesthesia in randomized trials
Treatment
Perioperative tropisetron versus placebo, other antiemetics, or combinations
Follow-up
not stated in the source
Study design
Systematic review and meta-analysis with trial sequential analysis
Funding
not stated in the source

The control groups pooled placebo, other antiemetics and combinations. The abstract does not state the number of trials or patients.

Read the original source
In vitro receptor assays: tropisetron is an alpha7 partial agonist; ondansetron is not

Cell study

Macor JE et al. Bioorg Med Chem Lett. 2001;11(3):319-21. PMID 11212100.

Receptor pharmacology identified tropisetron, a 5-HT3 receptor antagonist, as a potent and selective partial agonist at alpha7 nicotinic receptors. Two other 5-HT3 antagonists, ondansetron and LY-278,584, lacked high alpha7 affinity, so the nicotinic action is specific to tropisetron among the drugs tested.

Participants / model
In vitro receptor assays
Treatment
Not applicable
Follow-up
not stated in the source
Study design
Original mechanistic study of receptor affinity and partial agonism
Funding
not stated in the source

This is in vitro evidence, not a cognitive outcome.

Read the original source
PET: tropisetron, not ondansetron, lowered alpha7 tracer binding in healthy men

Human study

Ishikawa M et al. Clin Psychopharmacol Neurosci. 2011;9(3):111-6. PMID 23430308.

A single oral dose of tropisetron, but not ondansetron, lowered the total distribution volume of the alpha7 PET tracer [11C]CHIBA-1001, consistent with tropisetron binding alpha7 receptors in the living human brain. The abstract does not state the dose or the number of participants, and no cognitive endpoint was measured.

Participants / model
Healthy non-smoking men (number not stated in the abstract)
Treatment
Single oral dose of tropisetron or ondansetron (dose not stated in the abstract)
Follow-up
Single dose
Study design
Human PET receptor-occupancy study
Funding
not stated in the source

A receptor-occupancy result with no cognitive endpoint.

Read the original source
Preclinical: oocytes, rats and aged rhesus monkeys, not human cognition

Animal study

Callahan PM et al. Neuropharmacology. 2017;117:422-433. PMID 28259598.

In Xenopus oocytes expressing human receptors, tropisetron was a partial agonist at alpha7 (EC50 about 2.4 micromolar) and alpha7beta2 (about 1.5 micromolar) receptors, and low concentrations (10 and 30 nM) enhanced acetylcholine-evoked currents. Tropisetron (0.1 to 10 mg/kg) improved novel object recognition in young and aged rats, and in aged rhesus monkeys (0.03 to 1 mg/kg) raised long-delay matching accuracy 17% from baseline; combining doses of donepezil and tropisetron that were each ineffective alone gave a 24% change.

Participants / model
Xenopus oocytes with human receptors; young Sprague-Dawley rats; aged Fischer rats; aged rhesus monkeys
Treatment
Doses as stated; route not given in the abstract
Follow-up
not stated in the source
Study design
Original preclinical study of receptor currents, novel object recognition and delayed match-to-sample accuracy
Funding
not stated in the source

These are animal and cell findings, not human cognition. The route of administration is not given in the abstract.

Read the original source
Schizophrenia add-on trial: 40 patients, 8 weeks, P50 gating and sustained attention

Randomized controlled trial

Shiina A et al. Ann Gen Psychiatry. 2010;9:27. PMID 20573264.

Adjunctive tropisetron 10 mg/day (n = 20) versus placebo (n = 20) improved P50 auditory gating in non-smokers and the CANTAB rapid visual information processing (sustained attention) score. PANSS scores did not change. 33 patients completed. Quality of life improved in the whole sample but not in non-smokers.

Participants / model
40 adults with chronic schizophrenia taking risperidone 2 to 6 mg/day
Treatment
Oral tropisetron 10 mg/day added to risperidone, or placebo
Follow-up
8 weeks
Study design
Randomized double-blind placebo-controlled trial; P50 gating, CANTAB, PANSS, Quality of Life Scale
Funding
not stated in the source

A small trial in medicated patients with schizophrenia. It does not describe healthy adults.

Read the original source
Schizophrenia dose trials: 40 non-smoking patients each, 10 days and 1 day, RBANS gains

Randomized controlled trial

Zhang XY et al. Am J Psychiatry. 2012;169(9):974-81. PMID 22952075.

Ten days of oral tropisetron at 5, 10, or 20 mg/day (10 per arm) versus placebo improved overall RBANS cognitive scores at all three doses, and P50 gains correlated with cognitive gains. Two patients on 20 mg/day dropped out with adverse effects. A separate 1-day trial of the same design and size by the same group (PMID 32349117) reported higher RBANS total scores at 5 and 20 mg and higher immediate memory at 10 mg than placebo.

Participants / model
40 non-smoking adults with schizophrenia, P50 ratios above 0.5, on stable risperidone 3 to 6 mg/day (each trial)
Treatment
Oral tropisetron 5, 10, or 20 mg/day added to risperidone, or placebo
Follow-up
10 days (and 1 day in the companion trial)
Study design
Randomized placebo-controlled trials; RBANS cognitive battery, P50 gating, dropouts
Funding
not stated in the source

Short trials in medicated, non-smoking patients with schizophrenia, with 10 patients per arm.

Read the original source
Registry NCT00435370: 179 patients, 12 weeks, MATRICS 96 versus 95, no peer-reviewed report

Trial registry record

ClinicalTrials.gov record NCT00435370 (Baylor College of Medicine), results posted in the registry and read through the ClinicalTrials.gov API v2.

The registry posts results for 179 patients randomized to tropisetron 10 mg/day (n = 90) or placebo (n = 89), both with risperidone 6 mg/day, for 12 weeks (Chinese patients described as first-episode and drug-naive; 68 and 69 completed). The MATRICS composite at 12 weeks was 96 (SD 16) on tropisetron and 95 (SD 15) on placebo, and the registry reports an ANCOVA p below 0.05. No serious adverse events occurred in either arm (0 of 90, 0 of 89). A PubMed search on 9 October 2026 for tropisetron AND (MATRICS OR MCCB OR "12 weeks" OR "12-week") AND schizophrenia returned 0 records.

Participants / model
179 Chinese patients with schizophrenia
Treatment
Oral tropisetron 10 mg/day or placebo, each with risperidone 6 mg/day
Follow-up
12 weeks
Study design
Randomized trial with registry-posted results and no peer-reviewed report
Funding
not stated in the source

The largest tropisetron cognition trial in these records has registry-posted results only. The group means are near identical while the registry reports a p below 0.05, so the full analysis is needed before any conclusion is drawn.

Read the original source
Add-on meta-analysis: six trials, 311 patients, PANSS improved, constipation more common

Systematic review and meta-analysis

Kishi T et al. Neuromolecular Med. 2014;16(1):61-9. PMID 23896722.

Across six add-on trials (n = 311; three tropisetron, two ondansetron, one granisetron), 5-HT3 antagonists improved PANSS total (SMD -1.03, 95% CI -1.70 to -0.36; 5 studies, n = 261), negative (SMD -1.10), and general (SMD -0.70) scores, but not positive scores, with high heterogeneity (I2 73 to 84%). Constipation was more common than with placebo (RR 2.05, 95% CI 1.07 to 3.91; NNH 11), and dropouts did not differ. A 2026 Bayesian network meta-analysis of 30 trials (3128 participants; PMID 41321045) also found tropisetron 5 mg effective on PANSS total.

Participants / model
Adults with schizophrenia in add-on randomized trials
Treatment
Oral 5-HT3 antagonists added to antipsychotics
Follow-up
not stated in the source
Study design
Meta-analysis of six randomized add-on trials
Funding
not stated in the source

These are symptom scales, not cognitive tests, and the trials pooled three different 5-HT3 antagonists.

Read the original source
Cardiac surgery trial: 75 patients, lower troponin, CK-MB, TNF-alpha and LDH

Randomized controlled trial

Yu D et al. Front Med (Lausanne). 2022;9:690272. PMID 35425785.

In 75 patients having heart valve replacement with cardioplegic arrest, tropisetron 10 mg in 10 mL given right after anesthesia induction, versus 10 mL saline, reduced postoperative rises in cardiac troponin I (12 and 24 h), CK-MB (4, 12, and 24 h), TNF-alpha (4 and 12 h), and LDH (24 h), and raised IL-10 at 12 h.

Participants / model
75 adults having elective heart valve replacement
Treatment
Single dose of tropisetron 10 mg after anesthesia induction, or saline (route not stated in the abstract)
Follow-up
Postoperative markers to 24 hours
Study design
Randomized trial of myocardial injury markers and cytokines
Funding
not stated in the source

The only randomized trial with inflammatory-marker endpoints in patients among the records reviewed. Other anti-inflammatory evidence is in cultured human monocytes (PMID 22664143) and rodent models, and other non-nausea human trials measured pain, not inflammation (for example, a 418-patient fibromyalgia trial, PMID 11708570).

Read the original source
PK in 18 healthy volunteers: half-life 5.7 hours, bioavailability 0.60

Human study

Kees F et al. Br J Clin Pharmacol. 2001;52(6):705-7. PMID 11736884.

In 18 healthy volunteers, 5 mg oral tropisetron gave a mean Cmax of 3.46 ng/mL at 2.6 h and a half-life of 5.7 h; after 2 mg intravenously the half-life was 5.6 h, volume 678 L, and clearance 1800 mL/min. Oral bioavailability averaged 0.60 (range 0.27 to 0.99) and fell as CYP2D6 activity rose. In 13 healthy Korean subjects given 5 mg, mean AUC was 1.9-fold higher in carriers of one and 6.8-fold higher in carriers of two poor-metabolizer-associated CYP2D6 alleles than in wild-type carriers (PMID 12728290).

Participants / model
18 healthy volunteers; 13 healthy Korean subjects
Treatment
Single 5 mg oral capsule; single 2 mg intravenous bolus
Follow-up
Single doses
Study design
Clinical pharmacokinetic studies with CYP2D6 genotype comparison
Funding
not stated in the source

Single-dose studies in healthy volunteers. Exposure varies with CYP2D6 genotype.

Read the original source
PubChem: tropisetron and tropisetron hydrochloride identity

Chemical identity record

National Library of Medicine. PubChem compound records CID 656665 (tropisetron) and CID 656664 (tropisetron hydrochloride).

Tropisetron free base: PubChem CID 656665, C17H20N2O2, 284.35 g/mol, CAS 89565-68-4. Tropisetron hydrochloride, the salt in the Australian ampoules: CID 656664, C17H21ClN2O2, 320.8 g/mol, CAS 105826-92-4; 5.65 mg of the salt equals 5 mg of base. Former code ICS 205-930 (SDZ-ICS-930). Clinical doses are expressed as tropisetron base, and vendor powders may be either form.

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

Identity record only. Vendor powders may be either form.

Read the original source

Why is Tropisetron in A tier?

A fits an established antiemetic outside the US: Australia currently registers generic intravenous tropisetron for chemotherapy-induced and postoperative nausea and vomiting, and a 2024 meta-analysis supports its postoperative efficacy. No FDA-approved product was located and the originator licences were withdrawn in Ireland in 2000, so the data are strong for a narrow, regional use. The grade does not cover the cognition, anti-inflammatory and nicotine-profile claims.