Q.9 Write a note on addictive Drugs.
Answer:
Major categories of addictive drugs are:
1. Sedatives
(a) Introduction
These drugs interact with central nervous system to depress its activities. Sedative drugs have following effects
(b) Effects:
i. Induce dizziness
ii. Lethargy
iii. Slow brain function and depression
iv. Long term use of sedative induce suicidal thoughts
2. Narcotics
(a) Introduction
Narcotics are strong pain killers. These drugs are often prescribed in conjunction with other less potent pain killers (paracetamol or aspirin).
(b) Uses of Narcotics
i. These are used to relieve pain for patients with chronic diseases such as cancer.
ii. These are also used to relieve acute pain after operations.
iii. The abused narcotic i.e. heroin is a semi synthetic drug from morphine. It affects on central nervous system and causes drowsiness.
iv. Some people may abuse narcotics for ecstatic effects
v. Morphine and codeine are derived from poppy. Morphine is used to relieve pain.
vi. Heroin is prescribed as a strong analgesic under the name diamorphine in many western countries. It is used for acute pain such as in severe physical trauma, myocardial infarction, post surgical pain etc.

3. Hallucinogens 
(a) Introduction
Hallucinogens are the drugs that cause changes in perception, thought, emotion and consciousness.
(b) Groups
It has two groups:
i. Mescaline
Which comes from a cactus.
ii. Psilocin
Which comes from a mushroom.
(c) Effects
Physiologically, hallucinogens affects on:
i. Sympathetic nervous system.
ii. Causing dilation of pupils.
iii. Constriction of some arteries.
iv. Rise in blood pressure.
3. Marijuana (Hashish)
(a) Introduction
Marijuana (Hashish) is a hallucinogen which is smoked. It is the Marijuana most commonly used drugs in the world.
(b) Sources
It is obtained from the flowers, stems and leaves of the marijuana plant (Cannabis sativa) and (C. indica).
Effects
i. Small doses of marijuana result in a feeling of well-being that lasts two to three hours.
ii. High doses increases heart rate.
iii. It affects the production of sperms in men.
iv. It weakens the short term memory.