Triamterene contraindications

Also contraindicated for the treatment of hypertension in patients with the following conditions Type 2 diabetes with microalbuminuria serum creatinine greater than 2 mg/dL in males or greater than 1.8 mg/dL in females Ccr less than 50 mL/min concomitant use of potassium supplements or potassium-sparing diuretics (amiloride, spironolactone, or triamterene). 

Because the actions of triamterene and amiloride are independent of plasma aldosterone levels, their prolonged administration is likely to result in hyperkalemia. Both amiloride and triamterene are contraindicated in patients with hyperkalemia. Triamterene should not be given to patients with impaired renal function. Potassium intake must be reduced, especially in outpatients. A folic acid deficiency has been reported to occur occasionally following the use of triamterene. 

Contraindications Concurrent use of potassium supplements or potassium-sparing diuretics (such as amiloride, spironolactone, and triamterene), or strong inhibitors of the cytochrome P450 3A4 enzyme system (including ketoconazole and itraconazole), creatinine clearance less than 50 ml/min, serum creatinine level greater than 2 mg/dl in males or 1.8 mg/dl in females, serum potassium level greater than 5.5 mEq/L, type 2 diabetes mellitus with microalbuminuria... 

Triamterene is poorly soluble and may precipitate in the urine, causing kidney stones. Contraindications... 

Triamterene Indometacin Potentiation of nephrotoxicity, including subjects with normal renal function Combination contraindicated... 

The most serious side effect associated with the use of triamterene is hyperkalemia. For this reason, potassium supplements are contraindicated, and serum potassium levels should be checked regularly. Triamterene also is used in combination with hydrochlorothiazide. Here, the hypokalemic effect of the hydrochlorothiazide counters the hyperkalemic effect of the triamterene. Other side effects that are seen with the use of triamterene are nausea, vomiting, and headache. 

On the basis of the above findings, the manufacturer contraindicates the use of dofetilide with hydrochlorothiazide alone or in combination with triamterene. Given the increase in QT interval, a risk factor for torsade de pointes arrhythmia, this appears a prudent precaution. Further study is needed. Any diuretic that depletes serum potassium (such as the loop diuretics) might be expected to increase the risk of QT prolongation and torsade de pointes with dofetilide, and serum potassium should be monitored. ... 

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