[Dose-response relationship of xipamide in healthy subjects]

To establish a dose-effect relationship for the xipamide diuretic in double-blind trials 0, 5, 10, 20 and 40 mg of xipamide were administered to 5 groups of 6 to 14 healthy test persons in each group. Before, during and after the 15-d period of application all the blood electrolytes as well as the metabolism parameters of glucose, uric acid, cholesterol, neutral fats as well as creatinine and urea were determined. Similarly during the entire period of investigation the 24-h urine samples were collected daily and from these the electrolyte excretion as well as the endogenic creatinine clearance were determined. It was found that diuresis and natriuresis significantly enhanced in comparison with placebo were already achieved with 5 mg xipamide per day, they could no further be increased by higher doses. Much rather at 40 mg xipamide per day a significant hypokalaemia as well as a light hypercalcaemia developed. Independently of the dose, during the period of investigation a light, fully compensated hypochloraemic alkalosis developed. Regarding the metabolic processes a slight increase in the uric acid and cholesterol blood levels was observed, while the blood-sugar level, the triglycerides as well as the endogenic creatinine clearance remained unaffected. It can be concluded from the investigations that maximum natriuresis and diuresis can already be achieved with a daily xipamide dose of 5 mg, while side effects can be kept at a minimum.