Hydrochlorothiazide + Triamterene

Indications

Hydrochlorothiazide + Triamterene is used for: Hypertension, Oedema

Adult Dose

Hypertension 1-2 tablets/capsules (37.5-50 mg triamterene and 25 mg HCTZ) PO qDay 1 tablet (75 mg triamterene and 50 mg HCTZ) PO qDay Dosing considerations Monitor serum potassium Edema 1-2 tablets/capsules (37.5-50 mg triamterene and 25 mg HCTZ) PO qDay 1 tablet (75 mg triamterene and 50 mg HCTZ) PO qDay

Child Dose

Safety and efficacy not established

Renal Dose

Administration

Should be taken with food. Take after meals.

Contra Indications

severe renal or hepatic impairment, preexisting or drug-induced hyperkalemia, patients at risk of respiratory or metabolic acidosis. Lactation.

Precautions

Renal and hepatic impairment; cirrhosis; DM; hyponatraemia; hyperuricaemia; history of nephrolithiasis; depleted folic acid stores. Monitor electrolyte concentrations closely, especially potassium levels. Observe for signs of liver damage, blood dyscrasias or other idiosyncratic reactions. Discontinue treatment if urinary calculus is passed. Pregnancy and elderly. Lactation: Not recommended; discontinue drug or do not nurse

Pregnancy-Lactation

Pregnancy category: C Lactation: Not recommended; discontinue drug or do not nurse

Interactions

May enhance toxicity of digitalis glycosides, neuromuscular-blocking action of competitive muscle relaxants, effect of antihypertensives. Increased risk of postural hypotension w/ alcohol, barbiturates, opioids. K-depleting effect enhanced by corticosteroids, lithium, ACTH, carbenoxolone.

Adverse Effects

Side effects of Hydrochlorothiazide + Triamterene : Triamterene Jaundice, Weaknes, Headache, Azotemia, Dizziness, Fatigue, Xerostomia, Photosensitivity, Rash, Diarrhea, Nausea, Vomiting, Hyperuricemia, Hyper/hypokalemia, Interstitial nephritis Hydrochlorothiazide Anorexia, Epigastric distress, Hypotension, Orthostatic hypotension, Photosensitivity, Anaphylaxis, Anemia, Confusion, Erythema multiforme, Stevens-Johnson syndrome, Exfoliative dermatitis including toxic epidermal necrolysis, Dizziness, Hypokalemia and/or hypomagnesemia, Hyperuricemia

Mechanism of Action

Hydrochlorothiazide inhibits the reabsorption of Na and chloride in the distal tubules causing increased excretion of Na and water K and hydrogen ions. Triamterene is a potassium sparing diuretic which appears to act mainly on the distal renal tubules. It increases the excretion of Na and reduces the excretion of potassium. It adds to the natriuretic but reduces the kaliuretic effects of other diuretics. It is structurally similar to folate and has anti-folate activity.