Rifampicin achieves peak serum levels and maximal bioavailability when administered under which conditions?

• A With a fatty meal to enhance lymphatic absorption
• B At bedtime with milk to match circadian cortisol rhythm
• C Divided into three doses after meals to reduce gastric irritation
• D As a single morning dose on an empty stomach, 30 minutes before breakfast ✓

Explanation

Food substantially reduces rifampicin absorption, lowering peak serum concentration, so it is given as a single morning dose on an empty stomach, half an hour before breakfast. A single daily dose also maintains the high peaks needed for bactericidal activity and reduces resistance emergence. Divided dosing lowers peak concentrations and is avoided. Gastric upset from rifampicin is mild compared with the cost of impaired absorption.

Reference: Katzung's Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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