A pteridine that is used as a mild diuretic. .

ELPI - Pharmacology:

ELPI interferes with sodium reabsorption in the distal renal tubule by inhibiting sodium transport mechanisms directly. Specifically it inhibits the Na+/K+/2Cl- co-transporter. The result is an electrical-potential difference across the membrane that blocks the passive distal tubular secretion of potassium. Relative to other diuretics, triamterene has a unique mode of action as it inhibits the reabsorption of sodium ions in exchange for potassium and hydrogen ions at that segment of the distal tubule under the control of adrenal mineralocorticoids (especially aldosterone).

ELPI for patients

Information for Patients

To help avoid stomach upset, it is recommended that the drug be taken after meals.

If a single daily dose is prescribed, it may be preferable to take it in the morning to minimize the effect of increased frequency of urination on nighttime sleep.

If a dose is missed, the patient should not take more than the prescribed dose at the next dosing interval.

ELPI Interactions

Caution should be used when lithium and diuretics are used concomitantly because diuretic-induced sodium loss may reduce the renal clearance of lithium and increase serum lithium levels with risk of lithium toxicity. Patients receiving such combined therapy should have serum lithium levels monitored closely and the lithium dosage adjusted if necessary.

A possible interaction resulting in acute renal failure has been reported in a few subjects when indomethacin, a nonsteroidal anti-inflammatory agent, was given with triamterene. Caution is advised in administering nonsteroidal anti-inflammatory agents with triamterene.

The effects of the following drugs may be potentiated when given together with triamterene: antihypertensive medication, other diuretics, preanesthetic and anesthetic agents, skeletal muscle relaxants (nondepolarizing).

Potassium-sparing agents should be used with caution in conjunction with angiotensin-converting enzyme (ACE) inhibitors due to an increased risk of hyperkalemia.

The following agents, given together with triamterene, may promote serum potassium accumulation and possibly result in hyperkalemia because of the potassium-sparing nature of triamterene, especially in patients with renal insufficiency: blood from blood bank (may contain up to 30 mEq of potassium per liter of plasma or up to 65 mEq per liter of whole blood when stored for more than 10 days); low-salt milk (may contain up to 60 mEq of potassium per liter); potassium-containing medications (such as parenteral penicillin G potassium); salt substitutes (most contain substantial amounts of potassium).

ELPI may raise blood glucose levels; for adult-onset diabetes, dosage adjustments of hypoglycemic agents may be necessary during and after therapy; concurrent use with chlorpropamide may increase the risk of severe hyponatremia.

Drug/Laboratory Test Interactions

ELPI and quinidine have similar fluorescence spectra; thus, triamterene will interfere with the fluorescent measurement of quinidine.

ELPI Contraindications

Anuria, severe or progressive kidney disease or dysfunction with the possible exception of nephrosis. Severe hepatic disease. Hypersensitivity to the drug.

ELPI should not be used in patients with preexisting elevated serum potassium, as is sometimes seen in patients with impaired renal function or azotemia, or in patients who develop hyperkalemia while on the drug. Patients should not be placed on dietary potassium supplements, potassium salts, or potassium-containing salt substitutes in conjunction with triamterene.

ELPI should not be given to patients receiving other potassium-sparing agents such as spironolactone, amiloride hydrochloride, or other formulations containing triamterene. Two deaths have been reported in patients receiving concomitant spironolactone and triamterene or Dyazide. Although dosage recommendations were exceeded in one case and in the other serum electrolytes were not properly monitored, these two drugs should not be given concomitantly.

Generic name, Overdose, Half Life ELPI, Food Interactions, Chemical, etc..

ELPI see also

Brand Names containing Triamterene

Chemical structure:
N N N N N N N H H H H H H H H H H H C12H11N7 2D chemical structure C12H11N7 SVG | 2D structure Triamterene chemical names, chemical properties, classification C12H11N7