Triamterene and Hydrochlorothiazide - Clinical Pharmacology. Triamterene and Hydrochlorothiazide is a diuretic, antihypertensive drug product, principally due to its hydrochlorothiazide component; the triamterene component of Triamterene and Hydrochlorothiazide reduces the excessive potassium loss which may occur with hydrochlorothiazide use. A diuretic is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. There are several categories of diuretics. The Department of Health and Community Services provides a leadership role in health and community services programs and policy development for the province. Usual Adult Dose for Edema. Hydrochlorothiazide 25 to 50 mg-Triamterene 37.5 to 100 mg orally once a day Comments:-Patients who become hypokalemic on 50 mg of hydrochlorothiazide may be transferred directly to hydrochlorothiazide 50 mg-triamterene 75 mg orally once a day. PDR Drug Summaries are concise point-of-care prescribing, dosing and administering information to help phsyicans more efficiently and accurately prescribe in their practice PDR's drug summaries are available free of charge and serve as a great resource for US based MDs, DOs, NPs and PAs in patient practice.