If a drug's metabolism shifts from first-order kinetics to zero-order kinetics due to enzyme saturation in the liver, which consequence follows concerning drug clearance?

💡 Explanation

When enzymes are saturated, the drug's elimination rate becomes constant rather than proportional to the drug concentration. Therefore, clearance, which is volume of plasma cleared per unit time, decreases non-linearly as concentration increases, because the elimination mechanism is overwhelmed, rather than remaining constant or increasing.

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