Clinical tolerability of ibopamine hydrochloride (SB 7505)

The clinical tolerance of ibopamine hydrochloride (Sb 7505) was investigated in 12 volunteers. The drug was administered on alternate days (2nd, 4th, 6th, 8th, 10th, 12th), starting at 100 mg and increasing by 50 mg each time to reach 350 mg on the 12th day. On the other days (1st, 3rd, 5th, 7th, 9th, 11th and 13th) a placebo was given. Diuresis increased progressively with the dose, reaching a maximum increase of 88% after the last dose, and showing a small residual effect on each subsequent placebo day. Body weight showed a marginal change and decreased by 2% in the last two days of treatment. Heart rate, systolic, diastolic and mean blood pressure showed only marginal fluctuations of about 7% around the mean values, which were of little statistical and of no clinical significance. Haematological and biochemical parameters were not affected. No side effect was noticed. The dose of 350 mg may probably be increased without leading to side effects.