- Alcohol and spirit.
- Cannabis indica (Indian hemp).
- Pethidine and methadone.
- Morphine.
- Heroin.
- Cocaine.
- Amphetamine.
- Opium and its derivatives.
- Caffeine in Nescafe and kola nut.
- L.S.D. (Lysergic Acid Diethylamide.
The drugs have certain characteristics that make the individual continue using them:
a. There is an overpowering desire or need (compulsion) to continue taking a drug and to obtain it by all means.
b. Tendency to increase the dose, though some addict may remain on a stationary dose (Tolerance).
c. There is the appearance of a withdrawal syndrome when the drug is not taken (delirium tiremens).