Twenty women aged 45-55 years with mild-moderate hypertension were treated for 12 months with etozolin, a new loop diuretic. All patients concluded the study; resting systolic pressure was reduced from 164 +/- 3 to 145 +/- 3 mmHg; diastolic blood pressure dropped from 103 +/- 2 mmHg to 90 +/- 1 mmHg. No changes of blood glucose, blood nitrogen, serum Na+, K+, creatinine, cholesterol, triglycerides were observed, nor serious adverse reaction appeared. In conclusion, etozolin is a safe and effective antihypertensive agent in a selection of hypertensive patients highly sensitive to pharmacological side effects.