Zero order kinetics occur in following drug with high dose ?
**Core Concept**
Zero-order kinetics, also known as **non-linear kinetics**, occur when the rate of drug elimination is constant and independent of the drug's plasma concentration. This can happen with certain drugs at high doses. **Enzyme saturation** is a key factor in zero-order kinetics.
**Why the Correct Answer is Right**
At high doses, the drug's elimination pathways, such as **hepatic metabolism** or **renal excretion**, become saturated, leading to a constant rate of elimination regardless of the drug's concentration. This results in zero-order kinetics, where the rate of elimination is constant and does not increase with increasing dose.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it does not specify the correct drug or dose relationship.
**Option B:** Incorrect as it is not related to the concept of zero-order kinetics.
**Option C:** Incorrect because it does not describe the phenomenon of enzyme saturation.
**Clinical Pearl / High-Yield Fact**
A classic example of a drug exhibiting zero-order kinetics at high doses is **aspirin**. At low doses, aspirin follows first-order kinetics, but at high doses, its elimination becomes zero-order due to **saturation of hepatic enzymes**.
**Correct Answer:** D. Aspirin