All of the following have poor penetration in brain and eyes except
Glycopyrrolate, Tiotropium bromide, Isopropamide are Atropine substitute Quaternary compounds. These compounds are lipid insoluble and therefore have poor penetration in brain and eyes. Glycopyrrolate blocks the peripheral muscarinic side effects(caused by increased Ach levels) without causing unwanted central anticholinergic effects. Pilocarpine and Arecoline being teiary aminesare readily absorbed and can cross the blood-brain barrier.
Glycopyrrolate
Pilocarpine
Tiotropium bromide
Isopropamide
Pharmacokinetics