Hydrochlorothiazide Pharmacokinetics and Pharmacologic Effect: The Influence of Indomethacin

It is known that nonsteroidal antiinflammatory drugs such as indomethacin can attenuate the pharmacologic effect of loop diuretics such as furosemide and ethacrynic acid and that indomethacin may also reduce the pharmacologic response to chlorothiazide. To examine further this potential drug-drug interaction, we administered 50- an 100-mg single oral doses of hydrochlorothiazide with and without indomethacin to 10 healthy, normal subjects. We observed no significant influence of indomethacin to 10 healthy, normal subjects. We observed no significant influence of indomethacin either on the pharmacokinetics of hydrochlorothiazide or the pharmacologic response to this diuretic. The adsorption and disposition of hydrochlorothiazide demonstrate that this drug is rapidly absorbed and produces a diuretic and natriuretic response that peaks at approximately 2 hours after dosing and is essentially terminated 12 hours after dosing. There appeared to be no greater pharmacologic response to the 100-mg than to the 50-mg hydrochlorothiazide dose in the ten subjects in this study.