**Question:** Topical beta blocker is the drug of choice of –

A. Hypertension
B. Angina pectoris
C. Glaucoma
D. Myocardial infarction

**Core Concept:** Beta blockers are a class of medications that act on beta receptors in the body, primarily beta-1 receptors in the heart and smooth muscles. Topical beta blockers are designed to be applied directly to the affected area to provide local effects without systemic side effects.

**Why the Correct Answer is Right:**
Topical beta blockers are chosen for specific conditions due to their localized action. In the case of **C. Glaucoma**, beta blockers help reduce intraocular pressure by decreasing aqueous humor production, reducing the risk of optic nerve damage. This is the primary indication for topical beta blockers in glaucoma treatment.

**Why Each Wrong Option is Incorrect:**
1. **A. Hypertension** is a systemic condition, and systemic beta blockers are preferred for managing hypertension, which affects the entire body. Topical beta blockers may not achieve adequate blood pressure reduction.
2. **B. Angina pectoris** is a cardiovascular condition, and systemic beta blockers are typically used orally or intravenously to manage angina, not topically.
3. **D. Myocardial infarction** is a severe cardiovascular event, and systemic beta blockers are the first-line treatment for myocardial infarction to protect the heart muscle from further damage. Topical beta blockers are not used in this context.

**Clinical Pearl:**
Topical beta blockers are a valuable tool in the ophthalmologist's arsenal for managing glaucoma and related conditions. However, their application in managing hypertension, angina pectoris, and myocardial infarction is limited due to their localized action and lack of systemic effects. This understanding helps differentiate between systemic and topical medications, ensuring appropriate treatment options for various medical conditions.