Addiction

‘Addiction’ refers to the dependence on, or craving for things like tobacco, alcohol or a particular drug.

Reducing or avoiding intake of drug may lead to characteristic physiological or  psychological symptoms like tremor or anxiety.

Tobacco-Smoking

Dried leaves of the plant Nicotiana tabacum and N.rustica (Family - Solanaceae) - used as tobacco.

Use originated in America, smoked by Red Indians.

As stimulant Nicotine causes release of adrenaline leading to

• Faster passage of nerve impulse.
• Relaxation of muscle
• Increased heart rate and high B.P.
• Poisonous; the amount present in a cigarette if injected intravenously may kill the person; causes retardation of foetus growth in pregnant women.

Tobacco smoke contains : CO, polycyclic aromatic hydrocarbon, tar.

Polycyclic hydrocarbons are carcinogenic.

Harmful effects of smoking include respiratory diseases (lung cancer, bronchitis and emphysema) and cardiovascular diseases (coronary artery disease and peripheral vascular disease).

Smoke particles irritate the lungs airways causing excess production of mucus; may indirectly destroy the walls of the lung alveoli which coalesce which in turn reduce the lung efficiency and may cause lung cancer.

Mouth cancer is common in tobacco chewers.

Central Tobacco Research Institute is situated at Rajahmundry (A.P.).

Anti-tobacco day is May 31.

Alcoholism

Ethanol, a colourless liquid, from the fermentation of carbohydrates of yeast; an active constituent of alcoholic, beverages like beer (5%), wine(10%) and whiskey (40%).

Used as a solvent and antiseptic in medicine; rapidly absorbed and enters the blood stream within a few minutes.  

In low level causes facial flushing, talkativeness and increases confidence. In high level causes disturbed thinking, irritability, reduced self-control, slurred speech, drowsiness, difficulty in remaining upright.

Effect of alcohol on the CNS (brain and spinal cord) is as a depressant ; decreases CNS activity thus reducing anxiety, tensions and inhibitions.

In liver, converted to acetaldehyde, used by cells for energy; synthesis of  fat occurs and extra fat decreases the production of enzymes and structural proteins; as a result liver becomes a store house for fat instead of a metabolic centre.

Accumulation of fat results in ‘fatty liver syndrome’ leading to cirrhosis (replacement of liver cells by fibrous tissue).

Alcohol addiction lowers blood glucose levels, thus adversely affecting the brain.

Drugs

Drugs : French term drogue, a dry herb

These chemicals alter the body functions.

Physicians prescribe them to prevent or cure a disease or enhance the mental and physical welfare.

Some drugs bear a risk and the patient become dependent on them. This is called drug dependence.

Psychotropic drugs (mood - altering drugs) act on the brain and alter the behaviour, consciousness and powers of perception. Divided into four categories -

• Sedatives and tranquilizers
• Opiate narcotics
• Stimulants, and
• Hallucinogens.

Sedatives and tranquilizers

Have depressing effect on the activity of the brain.

May produce a feeling of calmness, relaxation or drowsiness. In high dose, induce sleep.

Tranquilizers reduce tension and anxiety without inducing sleep.

Opiate Narcotics

Opium obtained from the unripe seed pods of the poppy plant Papaver somniferum has an analgesic effect and may also reduce tension and anxiety, and lowers the blood pressure and breathing rate.

Opium and its derivatives like morphine, codeine and heroine are collectively called narcotic drugs.

Morphine has sleep and dream inducing properties.

Codeine milder than morphine is used in cough syrup.

Narcotics induce addiction if repeatedly used and haroine being most dangerous narcotic.

Brown sugar, opium derivative, chemically known as diacetyl-morphine hydrochloride, is more powerful analgesic than morphine.

Stimulants

Temporarily increase in mental alertness, self-confidence and excitement; also known as ‘mood elevators’.

Increase nerve activity by initiating the release of noradrenaline.

groups are - CNS stimulants (e.g.-amphetamines) and respiratory stimulants (e.g.-analeptic drugs).

CNS stimulants act on the reticular system in the brain stem, reduce drowsiness and increase alertness.

Respiratory stimulants act on respiratory centre in the brainstem.

Caffeine (in tea, coffee and cola) is the mildest stimulant. Amphetamines and cocaine are strong stimulants.

Cocaine is obtained from the leaves  of  Erythroxylon cocca.

‘Crack’, a purified form of cocaine, cause seizures and cardiac arrest.

Hallucinogens

Also called psychedelic drugs; include drugs of abuse like LSD, marijuana, mescaline and psilocybin.

Have strong effect on cerebrum and sense organs and take user to fantasy world thus giving false and temporary happiness.

Alter a person thought, feelings and perceptions.

LSD (lysergic acid diethylamide) one of the most dangerous hallucinogens; derived from Ergot fungus, Claviceps purpurea; produces ‘bad trip’, a person experiences panic, fear, nausea, dizziness and weakness.

Products of hemp plant, Cannabis sativus are bhang, marijuana, ganja, hashish-charas.

Simultaneous use of drugs and alcohol

• Alcohol + Barbiturates increase depressant effect.
• Alcohol + Antihistamines cause drowsiness.
• Alcohol + Valium increase sedative effect.
• Alcohol + Hashish decreased co-ordination
• Alcohol + Aspirin damage to gastric mucosa    

Additional Points

• Reserpine alkaloid obtained from roots of Rauwolfia serpentina (family - Apocyanaceae) is used for treatment of blood pressure, snake bite and mental disorders.
• Drugs belladona is extracted from the dried leaves and roots of Atropa belladona (family - Solanaceae) is a narcotic, diuretic and antispasmodic. Leaves contain atropine, used to dilate pupil of eye.