Generally speaking, which of the following types of medications does NOT have anti cholinergic properties?

• A. Anti-histamines
• B. Glaucoma medications
• C. Anti Psychotics
• D. Antidepressants

Answer: (B)

Anticholinergic effects come from drugs that block acetylcholine at muscarinic receptors, which leads to symptoms like dry mouth, urinary retention, constipation, blurred vision, and cognitive changes. Many drug classes are known for these effects: older antihistamines block muscarinic receptors, so they commonly cause anticholinergic side effects; some antipsychotics have strong antimuscarinic activity and can produce similar symptoms; and certain antidepressants, especially tricyclics, also block muscarinic receptors, contributing to anticholinergic effects. Glaucoma medications, by contrast, are not defined by blocking acetylcholine. They include cholinergic agents that mimic acetylcholine to improve fluid drainage, as well as other mechanisms such as beta-blockade, prostaglandin receptor agonism, or alpha-adrenergic effects to lower intraocular pressure. Because they don’t antagonize muscarinic receptors, they generally do not have anticholinergic properties.