A farmer visiting a orchard gets unconscious, excessive salivation , constricted pupils and fasciculation of muscles, treatment staed with
**Core Concept**
Organophosphate poisoning is a well-known occupational hazard, particularly in agricultural settings. This condition results from exposure to organophosphate compounds, which inhibit acetylcholinesterase, an enzyme responsible for breaking down acetylcholine, a neurotransmitter involved in muscle contraction and other physiological processes.
**Why the Correct Answer is Right**
Atropine is the recommended treatment for organophosphate poisoning due to its anticholinergic properties. Atropine acts as a competitive antagonist at muscarinic acetylcholine receptors, thereby counteracting the excessive acetylcholine activity caused by the inhibition of acetylcholinesterase. By blocking muscarinic receptors, atropine reduces the symptoms of organophosphate poisoning, including excessive salivation, constricted pupils, and muscle fasciculations.
**Why Each Wrong Option is Incorrect**
**Option B:** Neostigmine is an acetylcholinesterase inhibitor, which would exacerbate the symptoms of organophosphate poisoning rather than treating them.
**Option C:** Physostigmine is a reversible acetylcholinesterase inhibitor, which would also worsen the condition by increasing acetylcholine levels.
**Option D:** Adrenaline (epinephrine) is not the primary treatment for organophosphate poisoning and may even worsen the condition by causing tachycardia and hypertension.
**Clinical Pearl / High-Yield Fact**
In the context of organophosphate poisoning, atropine is often used in conjunction with pralidoxime (2-PAM), an oxime that reactivates acetylcholinesterase. However, pralidoxime should not be administered until atropine has been given, as it can cause severe muscle fasciculations and weakness if administered alone.
**✓ Correct Answer: A. Atropine**