Phenibut may cause sleepiness and slowed respiratory. Some drugs, known as sedatives, may bring about sleepiness and slowed breathing. Having phenibut with sedative drugs may cause respiration issues and/or far too much sleepiness. The genetic codon for phenylalanine was first found by J. Heinrich Matthaei and Marshall W. Nirenberg in https://chanceefczv.bmswiki.com/4861327/considerations_to_know_about_4_fma