What are the side effects associated with cholinergic agonists?

• A. miosis, dimming of vision, myopia, headache, increased salivation, lacrimation, increased risk of retinal tear and RD
• B. Mydriasis, blurred vision, dry mouth
• C. Conjunctival hyperemia only
• D. No systemic effects

Answer: (A)

Cholinergic agonists activate the parasympathetic system in the eye, so they stimulate pupil constriction and secretory glands. This leads to miosis and increased tearing and salivation, along with effects from ciliary muscle contraction. The constricted pupil reduces light entry, which explains dim vision; the ciliary muscle tightens for near focus, causing accommodation and often blurred distance vision or even a transient near-sighted shift (myopia). Headache can arise from ciliary muscle spasm and the strain of near focus with a constricted pupil. In eyes predisposed to retinal problems, the anterior segment changes and altered vitreoretinal traction from these drugs can slightly raise the risk of retinal tear or retinal detachment. So the combination of miosis, reduced vision, accommodation-related blur, plus increased secretions and potential retinal risk fits the classic side effect profile of cholinergic agonists.