Thiazides

Common adverse effects

• dehydration
• postural hypotension
• hyponatraemia, hypokalaemia, hypercalcaemia
• gout
• impaired glucose tolerance
• impotence

Rare adverse effects

• thrombocytopaenia
• agranulocytosis
• photosensitivity rash
• pancreatitis

Bendroflumethiazide

Bendroflumethiazide - mechanism of hypokalaemia:

• increased sodium reaching the collecting ducts
• activation of the renin-angiotensin-aldosterone

Bendroflumethiazide (bendrofluazide) is a thiazide diuretic which works by inhibiting sodium absorption at the beginning of the distal convoluted tubule (DCT). Potassium is lost as a result of more sodium reaching the collecting ducts. Bendroflumethiazide has a role in the treatment of mild heart failure although loop diuretics are better for reducing overload. The main use of bendroflumethiazide was in the management of hypertension but recent NICE guidelines now recommend other thiazide-like diuretics such as indapamide and chlortalidone.

Common adverse effects

• dehydration