Hydrafinil (9-Fluorenol)

Overview

Hydrafinil (9-fluorenol) is a non-peptide fluorene derivative and secondary benzylic alcohol (C₁₃H₁₀O, MW 182.22) investigated as a potential wakefulness-promoting agent structurally distinct from modafinil's diphenylmethyl-sulfinyl scaffold. It has no approved human indication and is not FDA-approved or approved by any regulatory body for human or veterinary use. Hydrafinil is listed as an S6.A Non-Specified Stimulant on the WADA Prohibited List; Section S6.A stimulants are prohibited in-competition only, so it is banned in-competition and athletes are subject to strict liability. It is sold online by research-chemical vendors for laboratory use only, not for human consumption.

Mechanism of Action

No mechanism is established by direct receptor or transporter binding data verifiable from primary literature. A 2012 Cephalon Inc. medicinal-chemistry paper (Dunn et al., PMID 22546675) reported that a fluorene-derived analog's wake-promoting activity in rats was attributed to an active circulating metabolite; secondary sources identify that metabolite as fluorenol and cite dopamine-transporter reuptake-inhibition IC₅₀ values (~9 µM for fluorenol vs ~3.7 µM for modafinil), but these specifics are not confirmed in the published abstract and should be treated as plausible but unverified.

Research Summary

No human efficacy or safety trials have been conducted. The only human data is a 2021 pilot pharmacokinetic/analytical study (Knoop et al., PMID 34378339) in which three healthy male volunteers received a single 50 mg oral dose of hydrafinil, with urine collected up to 72 hours post-dose to characterize Phase I/II metabolites (hydroxylated, glucuronidated, sulfo-conjugated) for anti-doping detection purposes; this study was designed solely for metabolite identification and does not establish safety, efficacy, or a validated dose. In rats, a Cephalon Inc. drug-discovery program screened fluorene-derived compounds as candidate next-generation modafinil agents; one analog ('compound 15') showed wake-promoting activity attributed to an active metabolite ('compound 3'), though the published abstract does not confirm compound 3's identity as fluorenol or provide potency data.

Reported Side Effects

• No established human toxicity or safety profile—not evaluated in controlled trials
• WADA-prohibited S6.A stimulant (in-competition); strict liability for athletes in-competition
• Unknown cardiovascular, hepatic, or neuropsychiatric risk
• Unregulated research chemical; purity and contaminants unknown
• No carcinogenicity or reproductive-toxicity data

Compare Hydrafinil (9-Fluorenol) with Others

Research References

• Fluoren-9-ol - PubChem Compound Summary (CID 74318).
• Wake promoting agents: search for next generation modafinil, lessons learned: part III. 2012. PMID 22546675.
• Mass spectrometric characterization of urinary hydrafinil metabolites for routine doping control purposes. 2021. PMID 34378339.
• World Anti-Doping Code International Standard Prohibited List (2026). 2026.

Frequently asked questions

Has Hydrafinil (9-Fluorenol) been independently lab-tested?

Disclosed Labs has collected 2 Certificates of Analysis (COA) for Hydrafinil (9-Fluorenol) from 1 independent testing lab. 1 vendor has submitted material for testing. Products average 99.0% tested purity across the corpus. Full testing data is available at https://www.disclosedlabs.com/peptides/hydrafinil/testing.

How does Hydrafinil (9-Fluorenol) work?

No mechanism is established by direct receptor or transporter binding data verifiable from primary literature. A 2012 Cephalon Inc. medicinal-chemistry paper (Dunn et al., PMID 22546675) reported that a fluorene-derived analog's wake-promoting activity in rats was attributed to an active circulating metabolite; secondary sources identify that metabolite as fluorenol and cite dopamine-transporter reuptake-inhibition IC₅₀ values (~9 µM for fluorenol vs ~3.7 µM for modafinil), but these specifics are not confirmed in the published abstract and should be treated as plausible but unverified.

What does the research say about Hydrafinil (9-Fluorenol)?

No human efficacy or safety trials have been conducted. The only human data is a 2021 pilot pharmacokinetic/analytical study (Knoop et al., PMID 34378339) in which three healthy male volunteers received a single 50 mg oral dose of hydrafinil, with urine collected up to 72 hours post-dose to characterize Phase I/II metabolites (hydroxylated, glucuronidated, sulfo-conjugated) for anti-doping detection purposes; this study was designed solely for metabolite identification and does not establish safety, efficacy, or a validated dose. In rats, a Cephalon Inc. drug-discovery program screened fluorene-derived compounds as candidate next-generation modafinil agents; one analog ('compound 15') showed wake-promoting activity attributed to an active metabolite ('compound 3'), though the published abstract does not confirm compound 3's identity as fluorenol or provide potency data.