Can you help me understand pilocarpine?

Lowers eye pressure. Pilocarpine is a classic drug used to lower the internal eye pressure as a treatment for glaucoma. It can also adjust the pupil to help prevent acute glaucoma attacks. It has a number of side effects and must be used frequently each day, so it has fallen out of favor due to more useful eyedrops now available. But it is still useful in some patients.