Which of the following is a main ocular side effect of alpha-2 agonists?

• A. Allergy development
• B. Low blood pressure
• C. Dizziness
• D. Headache

Answer: (A)

Understanding what often shows up in the eye with alpha-2 agonist glaucoma medicines helps explain why allergy development is the best choice. These drugs, like brimonidine and apraclonidine, can trigger an ocular allergic reaction in some patients. This manifests as conjunctival itching, redness, tearing, and irritation, which are classic signs of an allergic conjunctivitis or allergic response localized to the eye.

Systemic effects such as low blood pressure, dizziness, or headache can occur with alpha-2 agonists, but they reflect body-wide effects rather than an eye-specific issue. The question is asking for the main ocular side effect, and the eye-related allergic reaction fits that goal more directly than the systemic symptoms.