Answer
Valsartan reduces hydrochlorothiazide’s systemic availability by about 30% when taken together, but this interaction does not affect their combined use, as controlled trials showed a greater antihypertensive effect than either medicine alone or placebo.
Sources for this answer
- Co-Diovan 80/12.5 mg, 160/12.5 mg, 160/25 mg TabletsNovartis Pharmaceuticals UK Ltd · emc · SmPC §5.2 Pharmacokinetic properties · Version 28Document updated
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