Do you know each other? 1000 mg of amoxicillin for strep As for Americans doing drugs for the first time, the largest number of recent drug initiates were for marijuana (2.4 million people), nonmedical use of prescription painkillers (1.9 million), nonmedical use of tranquilizers (1.4 million), Ecstasy, or MDMA (0.9 million), followed by stimulants, cocaine and inhalants (between 0.6 million and 0.7 million).