Triamterene + HCTZ

What Is Triamterene and Hydrochlorothiazide ?

Each triamterene and hydrochlorothiazide capsule for oral use contains triamterene 37.5 mg and hydrochlorothiazide 25 mg. Hydrochlorothiazide is a diuretic/antihypertensive agent and triamterene is an antikaliuretic agent.

What are the uses of this medicine?

Triamterene and hydrochlorothiazide capsules, USP are indicated for:

• The treatment of hypertension or edema in patients who develop hypokalemia on hydrochlorothiazide alone.
• For those patients who require a thiazide diuretic and in whom the development of hypokalemia cannot be risked.
• This medicine is used alone or as an adjunct to other antihypertensive drugs, such as beta-blockers. Since triamterene and hydrochlorothiazide capsules, USP may enhance the action of these agents, dosage adjustments may be necessary.

How does this medicine work?

• The triamterene and hydrochlorothiazide capsule is a diuretic/antihypertensive drug product that combines natriuretic and antikaliuretic effects.
• Each component complements the action of the other.
• The hydrochlorothiazide component blocks the reabsorption of sodium and chloride ions, and thereby increases the quantity of sodium traversing the distal tubule and the volume of water excreted.
• Hydrochlorothiazide also decreases the excretion of calcium and uric acid, may increase the excretion of iodide, and may reduce glomerular filtration rate.
• The triamterene component of triamterene and hydrochlorothiazide capsules, USP exerts its diuretic effect on the distal renal tubule to inhibit the reabsorption of sodium in exchange for potassium and hydrogen ions.

Who Should Not Use this medicine ?

• Triamterene and hydrochlorothiazide capsules, USP should not be given to patients receiving other potassium-sparing agents such as spironolactone, amiloride, or other formulations containing triamterene.
• Potassium supplementation should not be used with triamterene and hydrochlorothiazide capsules, USP except in severe cases of hypokalemia.
• Triamterene and hydrochlorothiazide capsules, USP should not be given to patients with anuria, acute and chronic renal insufficiency or significant renal impairment.
• Triamterene and hydrochlorothiazide capsules, USP should not be used in patients with preexisting elevated serum potassium.
• This medicication should not be given to patients who have Hypersensitivity to either drug in the preparation or to other sulfonamide-derived drugs.

Is this medicine FDA approved?

• The combination was approved for medical use in the United States in 1965.
• In 2018, it was the 117th most commonly prescribed medication in the United States, with more than 6 million prescriptions.

How should this medicine be used?

• The usual dose of triamterene and hydrochlorothiazide capsules, USP is one or two capsules given once daily, with appropriate monitoring of serum potassium and of the clinical effect.

What are the dosage forms and brand names of this medicine?

• Triamterene and Hydrochlorothiazide Capsules, USP contain 37.5 mg triamterene and 25 mg hydrochlorothiazide, and are available.

This medicine is available in fallowing brand names:

• Dyazide® (containing Triamterene, Hydrochlorothiazide)
• Maxzide® (containing Triamterene, Hydrochlorothiazide)

What side effects can this medication cause?

Common possible side effects of this medicine include:

• Anaphylaxis, rash, urticaria, subacute cutaneous lupus erythematosus-like reactions, photosensitivity.
• Arrhythmia, postural hypotension.
• Diabetes mellitus, hyperkalemia, hypokalemia, hyponatremia, acidosis, hypercalcemia, hyperglycemia, glycosuria, hyperuricemia, hypochloremia.
• Jaundice and/or liver enzyme abnormalities, pancreatitis, nausea and vomiting, diarrhea, constipation, abdominal pain.'
• Acute renal failure
• Leukopenia, thrombocytopenia and purpura, megaloblastic anemia.
• Muscle cramps.
• Weakness, fatigue, dizziness, headache, dry mouth.
• Impotence, sialadenitis.

What special precautions should I follow?

• Caution should be exercised when administering triamterene and hydrochlorothiazide capsules, USP to patients with diabetes, since thiazides may cause hyperglycemia, glycosuria, and alter insulin requirements in diabetes.
• Thiazides should be used with caution in patients with impaired hepatic function.
• Hypokalemia is uncommon with triamterene and hydrochlorothiazide capsules, USP.
• Electrolyte imbalance, often encountered with this therapy with triamterene and hydrochlorothiazide capsules, USP when using high doses for prolonged periods or in patients on a salt-restricted diet.
• Triamterene and hydrochlorothiazide capsules, USP should be used with caution in patients with a history of renal stones.

What to do in case of emergency/overdose?

The signs and symptoms of overdosage(Electrolyte imbalance) include:

• polyuria
• nausea
• vomiting
• weakness
• lassitude
• fever
• flushed face
• hyperactive deep tendon reflexes

• If hypotension occurs, it may be treated with pressor agents such as levarterenol to maintain blood pressure.
• Induce immediate evacuation of the stomach through emesis or gastric lavage.
• There is no specific antidote.

Can this medicine be used 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.

What should I know about storage and disposal of this medication?

• Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature].
• Protect from light.
• Dispense in a tight, light-resistant container as defined in the USP, with a child-resistant closure.

• Dailymed label info on Triamterene + HCTZ
• FDA Triamterene + HCTZ