Final answer:
Pilocarpine is a high potency muscarinic agonist, charged medication primarily used in ophthalmology to treat eye disorders, including glaucoma, and as an antidote for certain types of poisoning.
Step-by-step explanation:
Pilocarpine is a medication used primarily within the specialty of ophthalmology. It is considered to have a high potency for its effects on ocular structures. This cholinergic compound is a muscarinic agonist and as such it is charged. Pilocarpine targets muscarinic receptors, which are a type of acetylcholine receptor protein; they are metabotropic receptors that can also bind muscarine. Its action on these receptors is responsible for reversing mydriasis (dilation of the pupil) often caused by other agents like phenylephrine, usually following an eye exam. By acting on the smooth muscle of the iris, pilocarpine constricts the pupil and through the contraction of the ciliary muscle, it facilitates the opening of trabecular meshwork near the base of the cornea. This allows for the drainage of aqueous humor from the anterior chamber of the eye, effectively reducing intraocular pressure associated with glaucoma.
It also serves as an antidote for muscarinic antagonist poisoning such as that caused by atropine or scopolamine, which are derived from plants of the Atropa genus, such as belladonna. The autonomic disruption caused by these poisons can be counteracted by pilocarpine's muscarinic agonist activity.