NSAID lacking anti-inflammatory action is:
**Core Concept:** Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) are a class of medications used to relieve pain, inflammation, and fever. They work by inhibiting the production of prostaglandins, which are hormone-like substances involved in pain, inflammation, and fever.
**Why the Correct Answer is Right:** The correct answer is "A," which refers to the option without anti-inflammatory action. In this case, we are discussing selective COX-2 inhibitors, which primarily target cyclooxygenase-2 (COX-2) enzyme, responsible for the production of prostanoids (prostaglandins). Selective COX-2 inhibitors reduce inflammation and pain but do not affect the production of thromboxane, which is essential for blood clotting. This selective inhibition results in a reduced risk of bleeding complications compared to nonselective NSAIDs.
**Why Each Wrong Option is Incorrect:**
A. While selective COX-2 inhibitors are indeed less likely to cause gastrointestinal side effects and bleeding complications compared to nonselective NSAIDs, they still possess anti-inflammatory action.
B. Nonselective NSAIDs inhibit both COX-1 and COX-2 enzymes, which results in reduced production of thromboxane, leading to an increased risk of bleeding.
C. Nonselective NSAIDs do have anti-inflammatory action, as they inhibit both COX-1 and COX-2 enzymes, which leads to decreased inflammation.
D. This option is incorrect because it does not specify the target enzyme or mechanism of action for the medication.
**Clinical Pearl:** Selective COX-2 inhibitors are beneficial for patients with a history of gastrointestinal bleeding or those at risk for this complication, as they minimize the risk of gastrointestinal adverse effects without compromising the anti-inflammatory benefits. However, they may still cause some gastrointestinal side effects, as they inhibit COX-2, which is involved in tissue repair and protection of the gastrointestinal mucosa.
**Correct Answer:** C. Nonselective NSAIDs possess anti-inflammatory action as they inhibit both COX-1 and COX-2 enzymes, leading to decreased inflammation.