Many, many American's self medicate to one extent or another. Caffeine, energy drinks, nicotine, and stimulants, help many people prepare for life's events of the day. Later, alcohol, tranquilizers, pot, and sleeping aides help millions "unwind" from our stressful daily life.
NPR ran an article about the drug war recently, and I include it here:
When It Comes To Drugs, A 'House' Deeply Divided