Which of the following is a selective COX-2 inhibitor?
**Core Concept**
Selective COX-2 inhibitors are a class of nonsteroidal anti-inflammatory drugs (NSAIDs) that specifically target the cyclooxygenase-2 (COX-2) enzyme, reducing inflammation and pain while minimizing gastrointestinal side effects. This is in contrast to non-selective NSAIDs that inhibit both COX-1 and COX-2 enzymes.
**Why the Correct Answer is Right**
Celecoxib is a selective COX-2 inhibitor that works by binding to the active site of the COX-2 enzyme, inhibiting its activity and subsequently reducing the production of prostaglandins. This mechanism of action is responsible for its analgesic, antipyretic, and anti-inflammatory effects. Celecoxib's selectivity for COX-2 over COX-1 helps minimize the risk of gastrointestinal side effects associated with non-selective NSAIDs.
**Why Each Wrong Option is Incorrect**
**Option A:** Ibuprofen is a non-selective NSAID that inhibits both COX-1 and COX-2 enzymes, making it a poor choice for patients at risk of gastrointestinal bleeding.
**Option B:** Naproxen is also a non-selective NSAID, similar to ibuprofen, and is not a selective COX-2 inhibitor.
**Option C:** Diclofenac is a non-selective NSAID that can cause gastrointestinal side effects due to its inhibition of COX-1.
**Clinical Pearl / High-Yield Fact**
Celecoxib is often used in patients with a history of gastrointestinal bleeding or ulcers, as its selective COX-2 inhibition reduces the risk of gastrointestinal side effects compared to non-selective NSAIDs.
**Correct Answer: C. Celecoxib**