Description
Phenibut is a depressant drug with anti-anxiety effects, with similarities to pregabalin and baclofen. Phenibut is used for the treatment of anxiety and insomnia in Russia, Ukraine, Belarus and Latvia. It is not approved for medical use in the UK, but is sold online as an unlicensed nootropic supplement.
Desirable Effects
- Anti-anxiety
- Euphoria
- Increased sociability
Undesirable Effects
- Headaches/dizziness
- Feeling/being sick
- Respiratory depression in combination with other depressants
What does it look like?
Tablets: Prescription tablets come in 250 mg or 500 mg doses. Tablets/capsules from nootropics or supplement vendors can have inconsistent doses between 0 and 1100 mg.
Liquid solution: 10 mg/mL for infusion
Power: Nootropics vendors typically sell phenibut in power form as either free amino acid (FAA) or salt (HCl)
Method of Use
Orally: swallowed as a tablet/capsule, powder dissolved and drunk as a liquid solution
Snorted: rarely snorted as a powder, avoided due to pain and swelling of the nostrils
Pharmacology
Phenibut has been classified as an atypical tranquiliser due to its mixed pharmacological action. Phenibut is a full agonist of the GABA-B receptor as well as a gabapentinoid, which block α2δ-1/2 calcium channel subunits (see Pregabalin for further information about gabapentinoids). Compared to baclofen and benzodiazepines, phenibut had considerably weaker anti-anxiety and tranquilising effects.
Alongside its GABA-mimicking and gabapentinoid effects, it has also been shown to stimulate dopamine receptors and block β-PEA in animal studies – a natural stimulating amine thought to contribute to anxiety.
There is not much research on the pharmacokinetics or toxicology of phenibut in animals or humans.
Interactions
The combination of phenibut with other depressants, such as opioids and benzodiazepines, is likely to carry the same increased risk of respiratory depression and overdose as other gabapentinoids. As opioid tolerance leads to more calcium channels in nerve cells, phenibut may also reduce opioid tolerance which can lead to accidental overdose. Drinking alcohol alongside taking phenibut can lead to increased sedative effects on the brain and body.
History
Phenibut was first synthesised by Prof Vsevolod Perekalin and colleagues at Herzen Pedagogic Institute, and introduced into medical use in the USSR in the 1960s. At the start of the 21st century, the niche prescription drug gained popularity within bodybuilding and online communities, and started appearing in unregulated ‘nutritional supplements’. As phenibut grew in popularity, more reports appeared of tolerance, dependence, and withdrawals similar to benzodiazepines and gabapentinoids. Since 2018, phenibut has become a controlled substance in Australia and several European countries.
Law
- Psychoactive Substances Act 2016
Possible offences
- Possession With Intent To Supply
- Maximum sentence – 7 years/fine/both
- Supply (including being concerned in supply, conspiracy to supply, aggravated supply and offer to supply)
- Maximum sentence – 7 years/fine/both
- Import/Export
- Maximum sentence – 7 years/fine/both
In practice maximum sentences are rarely used, for more detailed and accurate information go to our sentencing page.