What are the side effects of Phenibut (beta-phenylgamma-aminobutyric acid)?

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From the Research

Phenibut has several side effects, and its use should be approached with caution due to its potential for dependence and severe withdrawal symptoms, as evidenced by recent studies 1, 2.

Overview of Phenibut Side Effects

Phenibut is a central nervous system depressant that can cause a range of side effects, including:

  • Drowsiness
  • Dizziness
  • Nausea
  • Headaches At higher doses, users may experience more severe effects, such as:
  • Confusion
  • Coordination problems
  • Respiratory depression

Dependence and Withdrawal

Phenibut is also associated with significant withdrawal symptoms when stopped after regular use, including:

  • Anxiety
  • Insomnia
  • Tremors
  • Severe cases of psychosis or seizures Physical dependence can develop in as little as 1-2 weeks of regular use, with the typical dosage range being 250-1000mg, but tolerance develops quickly, leading users to increase their dose 3, 4.

Clinical Evidence

A systematic review of phenibut withdrawal found that it can cause severe symptoms, including delirium, hallucinations, and seizures, and that treatment strategies vary widely, with benzodiazepines or barbiturates with adjunctive baclofen being the most commonly used drugs for moderate to severe withdrawal 2. Another study found that exposure calls to a regional poison center regarding phenibut have increased over the past five years, with CNS depression being common and associated with significant clinical outcomes, including respiratory failure requiring intubation 5.

Recommendation

Due to the risks associated with phenibut, including its potential for dependence and severe withdrawal symptoms, it should be used with extreme caution, preferably under medical supervision, and never combined with other depressants like alcohol or opioids 1, 2.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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