bendroflumethiazide and potassium-sparing agents

C03EA13

Forms & Strengths

Combination product: Bendroflumethiazide 2.5 mg to 5 mg with a potassium-sparing diuretic (e.g., triamterene or amiloride) in fixed-dose oral tablets.

Adult Dosing

Hypertension: 1 tablet daily, adjusted based on clinical response and potassium balance.
Edema: 1 to 2 tablets daily in the morning, reduced for maintenance as tolerated.

Pediatric Dosing

Safety and efficacy in pediatric patients have not been established; use is generally not recommended.

Indications

Management of hypertension
Treatment of edema associated with congestive heart failure, hepatic cirrhosis, or corticosteroid and estrogen therapy, while minimizing hypokalemia risk

Mechanism of Action

Bendroflumethiazide inhibits sodium and chloride reabsorption in the distal renal tubules, increasing excretion of sodium, water, chloride, and potassium.
The potassium-sparing component acts on the distal renal tubule to inhibit sodium reabsorption and potassium excretion, mitigating thiazide-induced hypokalemia.

Contraindications

Anuria or severe renal failure (CrCl < 30 mL/min)
Hyperkalemia or concurrent use of potassium supplements
Addison's disease
Hypersensitivity to thiazides, sulfonamide-derived drugs, or the potassium-sparing agent

Adverse Reactions

Drug Interactions

Lithium: Reduced renal clearance, increasing risk of lithium toxicity.
ACE inhibitors, ARBs, or direct renin inhibitors: Increased risk of severe hyperkalemia.
NSAIDs: May attenuate the antihypertensive and diuretic efficacy and increase renal impairment risk.
Non-depolarizing skeletal muscle relaxants: Possible potentiation of neuromuscular blockade.
Antidiabetic agents: Thiazides may induce hyperglycemia, requiring dosage adjustment of hypoglycemic agents.

Curated Content: Needs Vetting Before Put to Clinical Use