(d) : Opiates are derived from opium along with their synthetic relatives. Opiates have narcotic, analgesic, sedative and astringent effects. Narcotic is a drug that induces stupor and relieves pain. Morphine is the main opium alkaloid, which is a strong analgesic and also has sedative and calming effect. It depresses respiratory centre and contributes to the fall in blood pressure. It can cause release of ADH, reduction in urine output, constipation and mild hyperglycaemia etc. It causes addiction. Barbiturates are substituted derivatives of barbituric acid. They reduce anxiety and induce sleep. Amphetamines are synthetic drugs which are strong stimulants. LSD (Lysergic acid diethylamide) is the most powerful hallucinogens that causes severe damage to central nervous system.