is phenobarbital a controlled substance
Controlled Substance â Phenobarbital is a Schedule IV drug. Dependence. Prolonged, uninterrupted use of barbiturates (particularly the short-acting drugs), even in therapeutic doses, may result in psychic and physical dependence.ach phenobarbital tablet contains 15 mg, 30 mg, 60 mg or 100 mg of phenobarbital. Inactive ingredients are as follows: 15 mg, 30 and 60 mg: Calcium Stearate, Colloidal Silicon Dioxide, Corn Starch, and Microcrystalline Cellulose.