short ppt on the topic antidote, easy for students from diploma and bachelor course . it explains definition , classification , mechanism of action with example .

1. ANTIDOTES
Shikha Agrawal
B.Pharm : Naraina Vidyapeeth Group
Of Institution

2. DEFINITION:
• According to WHO, an antidote is defined as a
therapeutic substance used to counteract the
toxic actions of a specified xenobiotic.
Antidotes reduce the overall burden of health
service in managing of poisoning cases.
• Antidote is a substance which is used to nullify
the harmful effect of poison .

3. CLASSIFICATION OF
ANTIDOTES:
According to mode of action, they are classified as
follows:
1. Physiological antidote
2. Chemical antidote
3. Mechanical antidote

4. PHYSIOLOGICAL ANTIDOTE
• It counteracts the effects of a poison by
producing the opposite pharmacological
effects.
e.g. ACHE inhibitor - morphine

5. CHEMICALANTIDOTE
• It interacts specifically with a toxicant or neutralize the
toxicant. e.g. Metal chelators combine with metals to
form complexes that can then be eliminated by the
kidneys.
• It mainly act by 2 mechanisms
1. Complex formation
2. Metabolic conversion.
Example : Nitrate interact with haemoglobin and cyanide
to form cyanomethaemoglobin, which is less toxic
than cyanide

6. MECHANICALANTIDOTE
• The agent which is used to interfere with
poison through physical properties, not change
their nature is known as physical antidote
• E.g : Activated charcoal (Universal antidote)