What is Phenibut HCl? Phenibut HCl is a tranquilizer and nootropic drug initially synthesized in Russia as a non-addictive alternative to psychoactive drugs like alcohol. The compound mimics the brain chemical gamma-aminobutyric acid (GABA) to reduce anxiety, improve sleep, and enhance cognition. While not approved by the FDA, but, people can buy Phenibut HCL powder … Continue reading Phenibut HCl Powder Advantages, dosage, and adverse effects (2025)