Does Caffeine Affect Phenibut?

Amount or timing may matter

The short answer

Phenibut is a GABA-B agonist with strong sedative effects. Caffeine opposes its calming mechanism and may mask sedation, increasing overdose risk.

How to arrange timing

Do not combine caffeine with phenibut. Caffeine may mask phenibut's sedation dangerously.

Reference

Reference noted for this food and supplement combination: Examine.com 2024

Important context

The effect can also change with food amount, supplement dose, product formulation, health conditions, and medication use. Ask a doctor or pharmacist first if you take medication, are pregnant or breastfeeding, or have a chronic condition.