Poison is toxic substance that causes disturbances in organisms, usually by a chemical reaction or other activity at molecular level when sufficient amount is being absorbed by the organism.
Classification of poisons:
- On the basis of origin:
Poison may be:
- Synthetic poison: Synthetic source may include various types of chemicals.
- Natural poison: Natural poison may be of vegetable, animal or mineral origin and
- On the basis of mechanism of action:
Poisons may be of following types;
They may be inorganic, organic or mechanical irritants.
- Inorganic irritants/substances:
They are either metallic or nonmetallic.
Phosphorus, chloride, iodine, bromine are examples
Copper, lead, mercury etc. are examples.
- Organic poisons:
They are either of:
- Animal origin: like venom of snake, scorpion, and insects etc.
- Plant origin: like ergot, aloe, capsicum, and castor seed etc.
- Mechanical irritant poison:
Powdered glass and diamond may sometime be used as mechanical irritant poison.
2. Corrosive poison:
Strong acids and bases are the examples of these types of poison. They destroy the organs and tissues internally as well as externally.
Examples: Hydrochloric acid, sulfuric acid and sodium hydroxide etc. may act as poison.
3. Neurotic poison:
They as the name indicates act on the nervous system (central or peripheral) and cause toxic effects.
Examples: Sedative, hypnotics, cocaine, nuxvomica and curare
4. Cardiac poisons:
Digitalis, stropanthus, and aconite are the examples.
5. Respiratory depressants:
Poisonous gases like carbon mono oxide (CO) and coal gas are the examples of respiratory depressant poisons. The patient dies due to the poor supply of oxygen.
6. Miscellaneous poisons:
Drugs like analgesics, antipyretics, antihistamines, and antidepressants may produce toxicity when consumed in higher doses and finally results in patient’s death.
Abid Ali @abidaliphm
Doctor of Pharmacy