INDICATIONS AND USAGE This fixed combination drug is not indicated for the initial therapy of edema or hypertension except in individuals in whom the development of hypokalemia cannot be risked.

Triamterene and hydrochlorothiazide tablets, USP are indicated for the treatment of hypertension or edema in patients who develop hypokalemia on hydrochlorothiazide alone.

Triamterene and hydrochlorothiazide tablets, USP are also indicated for those patients who require a thiazide diuretic and in whom the development of hypokalemia cannot be risked (e.g., patients on concomitant digitalis preparations, or with a history of cardiac arrhythmias, etc.).

Triamterene and hydrochlorothiazide tablets, USP may be used alone or in combination with other antihypertensive drugs, such as beta-blockers.

Since triamterene and hydrochlorothiazide tablets, USP may enhance the actions of these drugs, dosage adjustments may be necessary.

Usage in Pregnancy The routine use of diuretics in an otherwise healthy woman is inappropriate and exposes mother and fetus to unnecessary hazard.

Diuretics do not prevent development of toxemia of pregnancy, and there is no satisfactory evidence that they are useful in the treatment of developed toxemia.

Edema during pregnancy may arise from pathological causes or from the physiologic and mechanical consequences of pregnancy.

Thiazides are indicated in pregnancy when edema is due to pathologic causes, just as they are in the absence of pregnancy.

Dependent edema in pregnancy, resulting from restriction of venous return by the expanded uterus, is properly treated through elevation of the lower extremities and use of support hose; use of diuretics to lower intravascular volume in this case is illogical and unnecessary.

There is hypervolemia during normal pregnancy which is harmful to neither the fetus nor the mother (in the absence of cardiovascular disease), but which is associated with edema, including generalized edema, in the majority of pregnant women.

If this edema produces discomfort, increased recumbency will often provide relief.

In rare instances, this edema may cause extreme discomfort which is not relieved by rest.

In these cases, a short course of diuretics may provide relief and may be appropriate.

ADVERSE REACTIONS Side effects observed in association with the use of triamterene and hydrochlorothiazide tablets, other combination products containing triamterene/hydrochlorothiazide, and products containing triamterene or hydrochlorothiazide include the following: Gastrointestinal: jaundice (intrahepatic cholestatic jaundice), pancreatitis, nausea, appetite disturbance, taste alteration, vomiting, diarrhea, constipation, anorexia, gastric irritation, cramping.

Central Nervous System: drowsiness and fatigue, insomnia, headache, dizziness, dry mouth, depression, anxiety, vertigo, restlessness, paresthesias.

Cardiovascular: tachycardia, shortness of breath and chest pain, orthostatic hypotension (may be aggravated by alcohol, barbiturates or narcotics).

Renal: acute renal failure, acute interstitial nephritis, renal stones composed of triamterene in association with other calculus materials, urine discoloration.

Hematologic: leukopenia, agranulocytosis, thrombocytopenia, aplastic anemia, hemolytic anemia and megaloblastosis.

Ophthalmic: xanthopsia, transient blurred vision.

Hypersensitivity: anaphylaxis, photosensitivity, rash, urticaria, purpura, necrotizing angiitis (vasculitis, cutaneous vasculitis), fever, respiratory distress including pneumonitis.

Other: muscle cramps and weakness, decreased sexual performance and sialadenitis.

Whenever adverse reactions are moderate to severe, therapy should be reduced or withdrawn.

Altered Laboratory Findings Serum Electrolytes: hyperkalemia, hypokalemia, hyponatremia, hypomagnesemia, hypochloremia ( see WARNINGS and PRECAUTIONS ).

Creatinine , Blood Urea Nitrogen: Reversible elevations in BUN and serum creatinine have been observed in hypertensive patients treated with triamterene and hydrochlorothiazide.

Glucose: hyperglycemia, glycosuria and diabetes mellitus ( see PRECAUTIONS ).

Serum Uric Acid , PBI and Calcium: ( see PRECAUTIONS ).

Other: Elevated liver enzymes have been reported in patients receiving triamterene and hydrochlorothiazide.

Postmarketing Experience Non-melanoma Skin Cancer: Hydrochlorothiazide is associated with an increased risk of non-melanoma skin cancer.

In a study conducted in the Sentinel System, increased risk was predominantly for squamous cell carcinoma (SCC) and in white patients taking large cumulative doses.

The increased risk for SCC in the overall population was approximately 1 additional case per 16,000 patients per year, and for white patients taking a cumulative dose of ≥ 50,000 mg the risk increase was approximately 1 additional SCC case for every 6,700 patients per year.