Earliest drug used in acute angle closure glaucoma –
**Core Concept**
Acute angle closure glaucoma is a medical emergency that requires prompt treatment to reduce intraocular pressure (IOP) and prevent vision loss. The earliest drug used in this condition should be effective in rapidly lowering IOP.
**Why the Correct Answer is Right**
The correct answer is **Pilocarpine**. Pilocarpine is a muscarinic receptor agonist that causes miosis (pupil constriction), which helps to open the anterior chamber angle and reduce IOP. It is often used as the first-line treatment in acute angle closure glaucoma.
**Why Each Wrong Option is Incorrect**
**Option A:** Acetazolamide is a carbonic anhydrase inhibitor that can lower IOP, but it is not the earliest drug used in acute angle closure glaucoma. It is often used in conjunction with pilocarpine.
**Option B:** Timolol is a beta-blocker that can reduce aqueous humor production, but it takes longer to act compared to pilocarpine.
**Option C:** Atropine is an anticholinergic that can cause mydriasis (pupil dilation), which can worsen acute angle closure glaucoma.
**Clinical Pearl / High-Yield Fact**
In acute angle closure glaucoma, prompt treatment with pilocarpine can help to reduce IOP and prevent vision loss. However, it is essential to note that pilocarpine should be used with caution in patients with narrow angles or previous angle closure episodes, as it can precipitate further angle closure.
**Correct Answer:** C. Atropine