nortadalafil
updated
Nortadalafil is a tadalafil-related chemical, a synthetic intermediate in making tadalafil, found in sexual-enhancement products. It is promoted as a Cialis-like erection aid, but it is a different chemical with none of tadalafil's approval. No potency test of the exact compound or human trial exists, and the FDA found it undeclared in Wild Bull and warned of dangerous interactions with nitrate medicines. Graded F for documented hidden exposure with no established benefit or usable safety profile.
Small-molecule tadalafil analog
- Its chemical identity is distinct from tadalafil.
- FDA confirmed nortadalafil in Wild Bull and warned consumers not to use the product.
- Clinical efficacy, a usable dose, and a human half-life are not established by an adulterant finding.
Is nortadalafil generic Cialis?
Generic Cialis contains tadalafil. Nortadalafil is a different chemical and does not share that approval.
source: PubChem: nortadalafil chemical identity, National Library of Medicine. PubChem CID 9820973.
source: FDA Wild Bull hidden-ingredient alert, US FDA. Wild Bull contains hidden drug ingredient. December 26, 2023.
Do the papers establish potency or erectile benefit?
No exact-nortadalafil efficacy assay or clinical trial appears in the cited evidence. The synthetic paper identifies nortadalafil as intermediate 7a, while its PDE5 potency table tests other compounds.
Neither those derivatives’ nanomolar values nor tadalafil’s own value can be reassigned to nortadalafil.
A Vietnamese analytical study screened 92 selected samples and detected PDE5-related compounds in 20, including nortadalafil among the analytes. A Chinese 90-analyte method also validated its detection, but the positive real batches involved other compounds. These are chemical-exposure records, not treatment cohorts.
source: Beghyn et al., arylated tadalafil analogues, 2007, Beghyn T, Hounsou C, Deprez BP. Bioorg Med Chem Lett. 2007;17(3):789-92. PMID 17107795. DOI 10.1016/j.bmcl.2006.10.069.
source: Daugan et al., original tadalafil discovery series, Daugan et al., original tadalafil discovery series. https://doi.org/10.1021/jm0300577
source: Vietnamese LC-HRMS supplement analysis, 2021, Nguyen TO, Tran CS, Do TTH, Nguyen TMH, Bui QD, Bui CT, Nguyen HN, Dang TH, Dinh VC, Nguyen TAH, Le THH. Rapid Screening and Quantitative Determination of Illegal Phosphodiesterase Type 5 Inhibitors (PDE-5i) in Herbal Dietary Supplements. Journal of analytical methods in chemistry. 2021. DOI 10.1155/2021/5579500.
source: Chinese 90-analyte screen, 2024, Jin S, Wang Y, Ning X, Liu T, Liang R, Pei X, Cao J. UPLC-MS/MS-Based Target Screening of 90 Phosphodiesterase Type 5 Inhibitors in 5 Dietary Supplements. Molecules (Basel, Switzerland). 2024. DOI 10.3390/molecules29153601.
Does the Russian research establish a medical use?
The Russian report concerns identifying seized nortadalafil using chemical analysis. It does not test whether the compound works or is safe in people.
source: Russian forensic chemical investigation, Petrischeva DA et al. Butlerov Communications. 2018;55(9):146 to 154. DOI 10.37952/ROI-jbc-01/18-55-9-146.
What does the FDA alert establish?
FDA detected undeclared nortadalafil in Wild Bull and warned about potentially dangerous nitrate interactions. The alert does not give a dose-response, clinical benefit estimate or compound-specific injury rate.
The Russian forensic paper independently supports chemical identification. Neither seized material nor a supplement alert establishes a human half-life or an interaction-free exposure. N-substituted nortadalafil derivatives remain separate molecules.
Studies and sources
FDA Wild Bull hidden-ingredient alert
Official scientific or regulatory record
US FDA. Wild Bull contains hidden drug ingredient. December 26, 2023.
FDA reported undeclared nortadalafil and warned of potentially dangerous nitrate interactions. The alert gives no randomized outcome, dose-response, event incidence or toxicity comparison with tadalafil.
- Participants / model
- A marketed sexual-enhancement product
- Follow-up
- December 2023
- Study design
- Regulatory laboratory finding and consumer alert
PubChem: nortadalafil chemical identity
Government chemical identity database
National Library of Medicine. PubChem CID 9820973.
C21H17N3O4; molecular weight 375.4 g/mol.
- Participants / model
- Chemical record
- Follow-up
- Living database
- Study design
- Curated structure record
Formula and molecular weight establish the recorded structure, not the contents of a retail product or an effective dose.
Read the original sourceRussian forensic chemical investigation
Analytical identity or detection study
Petrischeva DA et al. Butlerov Communications. 2018;55(9):146 to 154. DOI 10.37952/ROI-jbc-01/18-55-9-146.
The English abstract describes chromatography/spectroscopy of seized nortadalafil and avanafil. It reports a chemical-identification study rather than a human pharmacokinetic or efficacy study.
- Participants / model
- Seized chemical substances; no human or animal treatment groups
- Follow-up
- Not a treatment study
- Study design
- Forensic chemical characterization
Primary abstract only
Read the original sourceBeghyn et al., arylated tadalafil analogues, 2007
Primary preclinical study
Beghyn T, Hounsou C, Deprez BP. Bioorg Med Chem Lett. 2007;17(3):789-92. PMID 17107795. DOI 10.1016/j.bmcl.2006.10.069.
The four-page paper identifies nortadalafil as synthetic intermediate 7a. Its bovine PDE5 assay evaluates tadalafil and arylated derivatives 6a and 8a through 18a, not 7a, so those nanomolar values cannot be assigned to nortadalafil.
Read the original sourceDaugan et al., original tadalafil discovery series
Primary preclinical study
Daugan et al., original tadalafil discovery series. https://doi.org/10.1021/jm0300577
The abstract describes a structure-activity series culminating in tadalafil, with strong stereochemical dependence. It does not report an exact nortadalafil potency value. Tadalafil’s own 5 nM result and rat blood-pressure effect cannot be reassigned to its precursor.
Read the original sourceVietnamese LC-HRMS supplement analysis, 2021
Analytical identity or detection study
Nguyen TO, Tran CS, Do TTH, Nguyen TMH, Bui QD, Bui CT, Nguyen HN, Dang TH, Dinh VC, Nguyen TAH, Le THH. Rapid Screening and Quantitative Determination of Illegal Phosphodiesterase Type 5 Inhibitors (PDE-5i) in Herbal Dietary Supplements. Journal of analytical methods in chemistry. 2021. DOI 10.1155/2021/5579500.
Ninety-two selected supplement and ingredient samples were screened; 20 contained detected PDE5-related compounds. Nortadalafil appeared among the analytes, sometimes with tadalafil or other compounds. The study measured product contents, not efficacy or adverse events in people.
Read the original sourceChinese 90-analyte screen, 2024
Analytical identity or detection study
Jin S, Wang Y, Ning X, Liu T, Liang R, Pei X, Cao J. UPLC-MS/MS-Based Target Screening of 90 Phosphodiesterase Type 5 Inhibitors in 5 Dietary Supplements. Molecules (Basel, Switzerland). 2024. DOI 10.3390/molecules29153601.
Nortadalafil was included in method validation. The eight positive batches among 286 contained sildenafil, 2-hydroxypropylnortadalafil, or N-ethyltadalafil; none was reported as a nortadalafil-positive batch. The related derivatives are separate compounds.
Read the original sourceWhy is nortadalafil in F tier?
F: documented hidden exposure without established clinical benefit, human pharmacokinetics, or a usable safety profile. The popular potency value was not confirmed in an exact-nortadalafil assay. FDA warns about nitrate interactions, but no exact-compound injury rate or comparison with other analogues exists.
how tiers are graded: methodology · every cited source · about reptides.
Research reference, not medical advice. Entries distinguish product labels, study doses and reported protocols. Check the linked source for the product, route and population.