Cisapride was withdrawn from market due to ?
**Core Concept**
Cisapride is a prokinetic agent that acts as a selective serotonin 5-HT4 receptor agonist, increasing gastrointestinal motility by enhancing acetylcholine release from enteric neurons.
**Why the Correct Answer is Right**
Cisapride was withdrawn from the market due to its association with severe cardiac arrhythmias, particularly QT interval prolongation, torsades de pointes, and sudden cardiac death. This is because cisapride can block the potassium channels in the heart, leading to a prolongation of the QT interval and an increased risk of arrhythmias.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while cisapride does have gastrointestinal side effects, its withdrawal was primarily due to cardiac concerns.
**Option B:** This option is incorrect because cisapride's mechanism of action is not related to its withdrawal from the market.
**Option C:** This option is incorrect because while cisapride can cause some CNS side effects, its withdrawal was not primarily due to these.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that QT interval prolongation can be caused by various medications, including antipsychotics, antibiotics, and antiarrhythmics, and can lead to life-threatening arrhythmias.
**Correct Answer:** C.