Method: Elderly people with isolated systolic hypertension (ISH) form the largest group of untreated hypertensive patients, despite the fact that a number of studies in recent years have drawn attention to the importance of an increase in systolic blood pressure values in the old age for the occurrence of cardiac and cerebral sequelae. To characterize the diuretic indapamide SR in the treatment of elderly multimorbid people with ISH (over the age of 60) 1503 patients (838 women, 665 men) with an average age of 67 years have been observed in a post-marketing surveillance study in practices of general and internal medicine. A subgroup of patients with diabetes and ISH has been registered separately. The patients with ISH have been compared with a group of elderly patients (831 women, 700 men) with the same average age of 67 years. Results. The dose of indapamide SR in the median observation period of three months was 1.5 mg per day. The systolic blood pressure reduction in ISH patients as well as in non-ISH patients was 25 mmHg. The mean reduction in diastolic blood pressure at the end of the observation period compared with baseline was approx. 9 mmHg in the ISH patients and 15 mmHg in the non-ISH patients. Thus, the diastolic blood pressure was dependent on the existing blood pressure measurements. The frequence of concomitant diseases was 0.6 % there was not any case of discontinuation of medication. Compared with the previous treatment, safety was assessed as clearly improved. The use of indapamide SR was metabolically and electrolytically neutral. As well in patients with diabetes the fasting blood glucose, the HbA(1C) the cholesterol and triglycerides are influenced positively. Conclusion: Indapamide SR 1.5 mg is very suitable for the long-term antihypertensive therapy in multimorbid elderly patients with ISH and usable in different patient groups. In the compared group of non-ISH patients a comparable decrease of blood pressure has been observed by a good safety, too.