Pilocarpine, sold under the brand name Pilopine HS among others, is a lactone alkaloid originally extracted from plants of the Pilocarpus genus.

[11] It works by activating cholinergic receptors of the muscarinic type which cause the trabecular meshwork to open and the aqueous humor to drain from the eye.

[16] It is used to prevent or treat dry mouth, particularly in Sjögren syndrome, but also as a side effect of radiation therapy for head and neck cancer.

[23] In 2021, the US Food and Drug Administration (FDA) approved pilocarpine hydrochloride as an eye drop treatment for presbyopia, age-related difficulty with near-in vision.

Pilocarpine has been known to cause excessive salivation, sweating, bronchial mucus secretion, bronchospasm, bradycardia, vasodilation, and diarrhea.

This movement causes the iris (which is located immediately in front of the lens) to also move forward, narrowing the Anterior chamber angle.

Pilocarpine can then be further purified by re-extracting the resulting solution with aqueous sulfuric acid then readjusting the pH to basic using ammonia and a final extraction by chloroform.

Pilocarpine is used to induce chronic epilepsy in rodents, commonly rats, as a means to study the disorder's physiology and to examine different treatments.

[31][32] Smaller doses may be used to induce salivation in order to collect samples of saliva, for instance, to obtain information about IgA antibodies.