TORASEMIDE - AN UPDATE OF ITS PHARMACOLOGICAL PROPERTIES AND THERAPEUTIC EFFICACY

The pharmacological properties and therapeutic use of the high-ceiling loop diuretic torasemide (torsemide) were previously reviewed in Drug s in 1991, the following being a re-examination of the role of the dru g in the light of data that have subsequently become available (partic ularly in the management of oedematous disorders). Torasemide produces a more prolonged water and electrolyte excretion than equipotent diur etic doses of furosemide (frusemide), but does not increase kaliuresis to the same extent. Dosages of torasemide of 2.5 to 5 mg/day do not a ffect plasma renin activity or aldosterone release to a clinically sig nificant extent, although torasemide 20mg increases plasma renin level s, angiotensin II activity and urinary dopamine and prostaglandin E ex cretion. Studies published since the previous review have confirmed th e efficacy of low dosages of torasemide (2.5 to 5 mg/day) in the treat ment of hypertension, and have shown it to be effective when administe red orally at a dosage of 5 to 20 mg/day in the management of congesti ve heart failure. Dosages of up to 400 mg/day increased urinary volume excretion and natriuresis in patients with chronic renal failure. Bod yweight and peripheral oedema were reduced by torasemide 10 to 200 mg/ day as monotherapy, and 5 to 20 mg/day when coadministered with spiron olactone, in patients with nephrotic syndrome. Dosages of 10 to 40 mg/ day, either as monotherapy or in conjunction with an aldosterone antag onist, reduced ascites, oedema and bodyweight in patients with hydropi cally decompensated liver failure.