Phenibut
Standing risks
| Risk | Recorded values | Confidence | Article section |
|---|---|---|---|
| Dangerous withdrawal, taper carefully |
| high | View in article: Dangerous withdrawal, taper carefully |
| Compulsive use risk, monitor frequency |
| high | View in article: Compulsive use risk, monitor frequency |
| High dependence, taper carefully |
| high | View in article: High dependence, taper carefully |
| Chronic toxicity, limit exposure |
| medium | View in article: Chronic toxicity, limit exposure |
Lethal interactions
| Combination | Type | Severity | Mechanisms | Confidence |
|---|---|---|---|---|
| GHB, GBL | Drug class | lethal | 2 | high |
| Opioids | Drug class | lethal | 2 | high |
Dangerous interactions
36 dangerous interactions recorded for this substance.
See the full interactions tableContraindications
| Condition | Severity | Note |
|---|---|---|
| Respiratory | ||
| respiratory disease | absolute | Phenibut may precipitate respiratory failure in individuals with pre-existing respiratory disease or obstructive sleep apnea. Approximately 50% of US intoxication cases required intubation, primarily in polysubstance contexts. |
| Psychiatric | ||
| substance use disorder | relative | 73% of patients presenting with phenibut withdrawal had prior history of alcohol or drug abuse. The self-medication pattern creates a high-risk pathway to dependence in this population. |
| anxiety disorders | relative | 60% of withdrawal patients had pre-existing anxiety or depression, suggesting elevated risk of dependence through self-medication pathways. |
| Hepatic | ||
| hepatic impairment | relative | While largely excreted unchanged (~63-65%), some hepatic metabolism occurs. Absence of CYP data prevents pharmacokinetic assessment in hepatic impairment. |
| Pregnancy & Breastfeeding | ||
| pregnancy | absolute | No human data on phenibut use during pregnancy or lactation. Given absence of safety data and known GABAergic developmental risks, use is contraindicated. |
| Other | ||
| concurrent CNS depressant use | absolute | The majority of serious phenibut intoxications involve polysubstance use. Combined use with opioids, benzodiazepines, or alcohol is potentially lethal. |