How is Pilocarpine as direct acting cholinergic agonist?

Alkaloid tertiary amine, stable to hydrolysis by acetylcholinesterase, uncharged penetrate CNS at therapeutic doses, exhibits muscarinic effects primarily in ophthalmology. Oral doses for treatment of Xerostomia (stimulate salivary and lacrimal secretions) resulting from radiation tx for cancer of head and neck. Opthalmic solution treats open angel glaucoma lowers intraocular pressure within few minutes following ocular instillation Causes contraction of iris sphincter results in miosis and contraction of ciliary muscles cause near focus vision. Causes marked diaphoresis (2-3 liters of sweat may be secreted) Enter brain and cause CNS disturbances