In six subjects the hypotensive action of metoprolol (Betaloc, Egis) after a dose of 166.7 +/- 47.1 mg and metipranolol (Trimepranol, Spofa) 21.7 +/- 3.7 mg was investigated. Betaloc influences after one month's administration the systolic blood pressure more effectively in a recumbent position and upright position and the diastolic pressure in a sitting position and after walking. The authors investigated also indicators of the circulation, blood sugar values, values of immunoreactive insulin, aldosterone and plasma renin activity after a single dose of 10 mg Trimepranol or 100 mg Betaloc. Betaloc caused a significant drop of the systolic blood pressure already after 15 minutes, Trimepranol after 30 minutes, in both instances the maximum effect was recorded after 45 minutes and persisted throughout the six-hour investigation. The diastolic blood pressure and heart rate were influenced only little. The blood sugar levels after Betaloc rose significantly during the first hour, after both drugs during the third hour. No correlation was found between changes of the blood sugar level and immunoreactive insulin levels. No differences were revealed as regards the effect on plasma renin activity and aldosterone levels.

Keywords: Blood Pressure /drug effects/; Drug Administration Schedule; Drug Therapy, Combination; Humans; Hypertension /blood/; Male; Metipranolol /administration & dosage/; Metoprolol /administration & dosage/; Middle Aged; Propanolamines /administration & dosage/