The prescription medications most commonly abused by people of any age are opioids (painkillers), depressants, and stimulants. Doctors prescribe opioids to relieve pain and, sometimes, to treat severe coughs and diarrhea. Depressants are used to treat anxiety and sleep disorders. The types of depressants that are most commonly abused are barbiturates (Secobarbital ,Mebaral and Nembutal) and benzodiazepines (Valium, Librium, and Xanax). Stimulants are used to treat narcolepsy (a sleep disorder), attention deficit hyperactivity disorder (ADHD), and depression that has not responded to other treatments. These medications increase alertness, attention, and energy. Stimulants include methylphenidate (Ritalin and Concerta), and amphetamines (Adderall). 
What is (are) Prescription and Illicit Drug Abuse ?