Final answer:
Atropine is an anticholinergic drug that acts as a muscarinic acetylcholine receptor antagonist to manage symptoms of nerve agent poisoning, and it can last for varying durations. The greatest inhibitory effects are on the respiratory and ophthalmic systems, and the antidote for atropine poisoning is a muscarinic agonist.
Step-by-step explanation:
Atropine is a well-known anticholinergic drug that acts as an antagonist to muscarinic acetylcholine receptors, blocking the effects of acetylcholine. It can work both centrally and peripherally, but some synthetic anticholinergics, like biperiden, are more effective centrally as they cross the blood-brain barrier more easily.
Atropine's therapeutic application includes managing the symptoms of nerve agent poisoning, especially by reducing excessive bronchial secretions. The duration it lasts can vary depending on the dose and the individual's physiology.
Anticholinergic drugs reduce the activity of the parasympathetic nervous system and the drug's greatest inhibitory effects are on the respiratory and ophthalmic systems where it reduces secretions and dilates pupils, respectively.
As for the antidote to atropine poisoning, the correct answer is a muscarinic agonist, which works against the anticholinergic effects of atropine. Finally, drugs that have anti-anxiety effects are typically not in the category of muscarinic agonists or anticholinergic but may be associated with the sympathetic or parasympathetic systems as sympatholytic or sympathomimetic agents.