Why does drug dosage adjustments based on patient weight fail when treating a highly lipophilic drug exhibiting extensive tissue binding?

💡 Explanation

The assumption that weight correlates linearly with drug distribution volume fails for lipophilic drugs because tissue binding sequesters the drug, creating a distribution volume unrelated to overall body weight; therefore, dosage based on weight alone is unreliable, rather than clearance or bioavailability being the dominant factors.

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