Certified Ophthalmic Medical Technologist (COMT) Practice Exam

Which type of drug is known to cause bilateral constriction of the pupils?

1. Antidepressants

2. Glaucoma miotics

3. Beta-blockers

4. Antihistamines

The correct answer is: Glaucoma miotics

Bilateral constriction of the pupils, also known as miosis, is primarily associated with the use of glaucoma miotics. These medications are specifically designed to treat glaucoma by reducing intraocular pressure, and they accomplish this by causing the muscles of the iris to contract, thus reducing the size of the pupil. Miotic agents include drugs such as pilocarpine, which stimulate the parasympathetic nervous system. This response leads to constriction of the pupil and can help improve the outflow of aqueous humor, consequently lowering the pressure within the eye. In contrast, antidepressants, beta-blockers, and antihistamines generally do not have a significant effect on pupil size that would lead to bilateral constriction. Antidepressants can sometimes cause pupil dilation (mydriasis), beta-blockers typically do not affect pupil size in a manner that would lead to constriction, and antihistamines may lead to pupil dilation as well due to their anticholinergic effects. Thus, glaucoma miotics are clearly identified as the type of drug responsible for bilateral pupil constriction.