Final answer:
Pilocarpine is a commonly used miotic drug that works as a muscarinic agonist to treat eye disorders such as glaucoma and also serves as an antidote to atropine or scopolamine poisoning.
Step-by-step explanation:
Pilocarpine is the most commonly used miotic topical drug for treating disorders of the eye. It acts as a nonspecific muscarinic agonist, which helps alleviate conditions such as glaucoma by constricting the pupil and assisting with the drainage of aqueous humor to reduce intraocular pressure. This is in contrast to drugs like atropine and scopolamine, which are muscarinic antagonists derived from the Atropa genus and have been historically used for their pupil-dilating properties. Pilocarpine serves as an antidote to atropine or scopolamine poisoning by reversing their anticholinergic effects.