A drug X has affinity to bind with albumin and Y has 150 times more affinity to bind with albumin than X. TRUE statement is-
**Core Concept**
The question is testing the understanding of drug-protein binding, specifically the affinity of drugs for albumin. Albumin is a plasma protein that binds to various drugs, affecting their distribution, metabolism, and elimination. The affinity of a drug for albumin is a critical factor in determining its pharmacokinetic properties.
**Why the Correct Answer is Right**
The correct answer is based on the principle that a drug with higher affinity for albumin will be more extensively bound to the protein, resulting in a lower free fraction of the drug. In this case, drug Y has 150 times more affinity for albumin than drug X. This means that Y will be more extensively bound to albumin, resulting in a lower free fraction of Y compared to X. This is a critical factor in determining the pharmacokinetics and pharmacodynamics of the drugs.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not provide any information about the relationship between the affinities of X and Y for albumin.
**Option B:** This option is incorrect because it suggests that X and Y have equal affinity for albumin, which contradicts the statement that Y has 150 times more affinity for albumin than X.
**Option C:** This option is incorrect because it suggests that Y has a lower affinity for albumin than X, which is the opposite of the correct statement.
**Clinical Pearl / High-Yield Fact**
When a drug has a high affinity for albumin, it may result in a longer half-life and reduced clearance, as the bound drug is not available for metabolism and excretion. This can lead to increased drug accumulation and potential toxicity.
**Correct Answer:** D.