Phenibut and Ketamine Therapy | Tovani Health
Anvifen (Phenibut) (also: Noofen, Fenibut) — GABA-B agonist (gray-market 'nootropic'; Soviet-era anxiolytic, not FDA-approved)
Verdict at Tovani Health
Real dependence/withdrawal liability and sedative stacking — coordination required.
Phenibut alongside ketamine therapy requires individual evaluation. Phenibut is a GABA-B agonist (structural analog of baclofen) sold as an over-the-counter 'nootropic' or anxiolytic supplement in the US but is a Soviet-era prescription drug elsewhere. Two real concerns: (1) sedative stacking with ketamine's CNS effects; (2) phenibut has documented dependence and severe withdrawal syndromes (anxiety, insomnia, agitation, seizures, psychosis) that mimic and worsen during periods of stress — KAP session day is not the time for an inadvertent withdrawal episode. We evaluate dose, frequency, and duration of use, and may ask for a tapered hold or coordinate session timing with a phenibut dosing plan. Patients sometimes don't realize phenibut has these properties because it's sold as a supplement.
If you take Anvifen regularly and are considering at-home ketamine therapy, eligibility depends on your specific situation — we evaluate case by case. This page covers the brief pharmacologic context and what we do at intake.
How Anvifen interacts with ketamine
Phenibut is a GABA-B receptor agonist (similar mechanism to baclofen) with additional dopaminergic and alpha-2-delta calcium channel activity at higher doses. Crosses the blood-brain barrier via its phenyl ring. Renally cleared, long-acting (12+ hours).
What we do at intake
Disclose dose (per dose and per week), frequency, and how long you've been using it. We may suggest a coordinated taper or hold before sessions — never stop phenibut abruptly if you've been on it daily, withdrawal is real.
Bottom line
Phenibut alongside ketamine therapy requires individual evaluation. Phenibut is a GABA-B agonist (structural analog of baclofen) sold as an over-the-counter 'nootropic' or anxiolytic supplement in the US but is a Soviet-era prescription drug elsewhere. Two real concerns: (1) sedative stacking with ketamine's CNS effects; (2) phenibut has documented dependence and severe withdrawal syndromes (anxiety, insomnia, agitation, seizures, psychosis) that mimic and worsen during periods of stress — KAP session day is not the time for an inadvertent withdrawal episode. We evaluate dose, frequency, and duration of use, and may ask for a tapered hold or coordinate session timing with a phenibut dosing plan. Patients sometimes don't realize phenibut has these properties because it's sold as a supplement.
Ready to find out if at-home ketamine fits your situation?
We’ll note that you’re on Anvifen (Phenibut) at intake. The eligibility check takes 5 minutes and gives you an honest answer about whether at-home ketamine fits your specific situation.
FL and NJ residents only. Benjamin Soffer, DO — Tovani Health.
Clinically reviewed
Reviewed by Benjamin Soffer, DO on May 23, 2026. Dr. Soffer is a board-certified physician (American Board of Internal Medicine) licensed in Florida and New Jersey, prescribing at-home ketamine therapy through Tovani Health.
This page is general information about how this medication interacts with at-home ketamine therapy at Tovani Health. It is not a substitute for medical advice from your prescribing physician about your specific situation. Always discuss medication changes with the doctor who prescribed them.