The influence of amiloride on the therapeutic and metabolic effects of carbenoxolone in patients with gastric ulcer. A double-blind controlled trial.

Patients with benign gastric ulcer were treated for four weeks with carbenoxolone sodium as Biogastrone tablets 100 mg three times a day, and if the ulcers were not healed at 4 weeks treatment was continued for a further 4 weeks. Fifty two patients entered the trial, and 12 were withdrawn. In 17 patients who were randomly allotted double-blind additional dummy tablets 16 of their ulcer healed completely endoscopically, whereas of the 23 patients given additional amiloride 5 mg three times a day only 14 ulcers healed, a significant reduction in ulcer healing. The clinical (weight gain and oedema) and metabolic (hypertension, hypokalaemia and hypernatraemia) side-effects were reduced by the active amiloride therapy, but serum carbenoxolone levels were not affected. Thus the potassium-retaining diuretic amiloride, like the aldosterone antagonist spironolactone, markedly reduces both the ulcer-healing and the metabolic side-effects of carbenoxolone sodium, and should not be used together with it in the treatment of peptic ulcer.