Which class of antidepressants is known for anticholinergic ocular effects?

• A. TCAs (Elavil, imipramine)
• B. 1st gen oral antihistamines (Benadryl)
• C. Phenothiazines (antipsychotics)
• D. Ritalin (methylphenidate)

Answer: (A)

Anticholinergic effects in the eye come from blocking muscarinic receptors in the eye, which leads to pupil dilation and loss of accommodation (cycloplegia). Tricyclic antidepressants have strong anticholinergic properties, so they commonly cause blurred vision from cycloplegia, dry eyes, and photophobia. This makes them the class most notably associated with ocular anticholinergic effects, and they can pose a risk for individuals with narrow-angle glaucoma due to the potential for angle-closure symptoms.

First-generation antihistamines do have anticholinergic effects, but they’re not antidepressants, so they don’t fit the prompt. Phenothiazines can have ocular effects as antipsychotics, but their primary ocular concerns aren’t the classic muscarinic-blockade–induced blurred vision. Methylphenidate is a stimulant with different side-effect Profile and lacks significant anticholinergic ocular effects.