Fall in systolic blood pressure due to metamizol (dipyrone, noramidopyrine, novaminsulfone). Results from the Comprehensive Hospital Drug Monitoring Berne (CHDMB).

A fall in systolic blood pressure which was not accompanied by any other symptoms of anaphylactic shock was first observed in 1972 and 1973 by our team in four patients after they had received metamizol-containing drugs parenterally. Of the 17,407 patients monitored from 1974-1981, ten further cases exhibited a fall in systolic blood pressure within minutes up to six hours after intravenous administration of metamizol. In all of these cases, a causal relationship between drug administration (0.5-2.5 g) and the reaction described was considered 'likely' or even 'definite'. During the same period, 67 arterial hypotensive incidents were registered in connection with other drugs. Between 1976 and 1981, 7 out of 15,678 patients monitored in the Comprehensive Hospital Drug Monitoring Berne (CHDMB) showed this adverse reaction. In relative figures, this represents 0.34% of the 2,053 patients who received parenteral treatment with a metamizol preparation.