Table 1

Diuretics used in the treatment of hypertension

ClassExample(s)Mechanism(s)Optimal dose (mg)Duration of action (h)AdvantagesDisadvantagesComments
GFR, glomerular filtration rate.
ThiazidesHydrochlorothiazideNatriuresis12.5–25.0 mg once daily6–12Potentiates other antihypertensivesHypokalaemiaEspecially effective in black patients, the obese, and the elderly
ChlorothiazideVasodilatation125–250 mg once daily6–12Hyperuricaemia
Bendrofluazide1.25–2.5 mg once daily6–12Low costHypercholesterolaemia
Trichlorothiazide1–2 mg once daily6–12Proven end organ efficacyHyperglycaemiaMediated via low K+
Thiazide relatedChlorthalidoneNatriuresis12.5–25.0 mg once daily6–12Lasts 24–48 hHypokalaemiaEspecially effective in black patients, the obese, and the elderly
IndapamideVasodilatation1.5–2.5 mg once daily16–36Works even if GFR is below 50 ml/minHyperuricaemia
Metolazone0.5–2.5 mg once daily18–25Works even if GFR is below 50 ml/minHypercholesterolaemia
K+ sparingSpironolactoneNatriuresis25–100 mg once daily3–5 daysSpares K+GynaecomastiaHigher doses in primary hyperaldosteronism
Triamterene25–50 mg once daily or twice daily8–12No effect on glucose, uric acid, or lipidLittle hypotensive effect on its ownUse with caution in patients with renal dysfunction
Amiloride5 mg once daily6–24
LoopFrusemideNatriuresis10–40 mg twice daily4–5More potent diuresisHypokalaemiaLess effective antihypertensive effects despite greater diuresis
Bumetanide0.5 mg twice daily4–5Hyperuricaemia
Ethacrynic acid25 mg once daily4–8Hypercholesterolaemia