Double-blind clinical evaluation of dimetophrine in chronically reduced arterial tension

Summary Thirty in-patients with chronically reduced arterial blood pressure and relevant subjective symptoms were treated over a 15-day period with oral doses of either 400 mg dimetophrine twice daily or placebo, according to a prospective, randomized, double-blind design. Systolic and diastolic blood pressures and heart rate were monitored at 5-day interval: subjective specific symptoms (scored 0 to 3 in order of increasing severity), haematology and haematochemistry were recorded before and after treatment. Both systolic and diastolic blood pressures increased significantly after dimetophrine all through the observation period. After 5 days, systolic blood pressure had already reached significantly higher values in comparison with the placebo-treated group, as did diastolic blood pressure by the 10th day. Overall, during the observation period, an increase from 82.7±1.0to 112.3±2.1 mmHg was observed in systolic and from 54.3±1.3 to 62.7±1.4 mmHg in diastolic blood pressure with dimetophrine, whereas with placebo, systolic blood pressure increased from 80.4±1.5 to 93.7±2.9 mmHg and diastolic blood pressure remained unchanged (53.3±1.4 mmHg). Concomitantly, heart rate decreased significantly with dimetophrine from 88.1±2.5 to 77.2±1.4 beats/min, whereas it remained almost unchanged with placebo (from 83.9±2.5 to 80.0±1.9 beats/min). The associated symptoms (asthenia, paleness, drowsiness, fatigue, sweating, vertigo and headache) were largely relieved by dimetophrine (70.0% decrease) but not by placebo (37.4%). All symptoms except drowsiness and vertigo were reduced to a significantly larger extent with dimetophrine than with placebo. Subjective symptoms or variations in haematology or haematochemistry suggestive of possible side-reactions were not observed with either treatment. There was a significant decrease in cholesterol and in free fatty acids, and increased hemoglobin after treatment with dimetophrine. Thus, dimetophrine restored normal arterial blood pressure and relieved the associated symptoms without the risk of induced hypertension, tachycardia and ventricular arrhythmia, usually concomitant with non-specific treatments. It is concluded, therefore, that oral dimetophrine is particularly suited for causal treatment of patients complaining of symptoms of mild to moderate chronically reduced blood pressure.