Answer
Phenylephrine in Benylin Cold & Flu Max Strength Capsules has reduced gastrointestinal bioavailability because of irregular absorption and first-pass metabolism by monoamine oxidase in the gut and liver.
Sources for this answer
- Benylin Cold & Flu Max Strength Capsules, hardMcNeil Products Ltd · emc · SmPC §5.2 Pharmacokinetic properties · Version 12Document updated
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