Time course of the anti-oedematous effect of O-(beta-hydroxyethyl)-rutosides in healthy volunteers.

O-(beta-hydroxyethyl)-rutosides (HR) is used for the treatment of disorders of the venous and microcirculatory systems. In order to evaluate the time course of its activity, the effect of HR on a provocation model of orthostatic oedema in healthy volunteers was used. After a 2 week placebo run-in period, 16 healthy volunteers were randomized to HR (2 tablets of 500 mg/day) of placebo for a further 3 weeks, in a double-blind parallel design. Oedema was provoked by standing motionless for 1 h, with measurement of leg volume before and afterwards. The procedure was undertaken at entry to the study and then weekly during the entire 5 week period. There were no significant differences in the extent of oedema produced by the orthostatic challenge during the 2 week run-in period or in the subjects who continued on placebo (approximately 90 arbitrary units i.e. approximately 48 ml). During the 3 week treatment with HR, however, there was a progressive reduction (-1.1, -5.9, and -7.6 arbitrary units after 1, 2, and 3 weeks, respectively) in the volume of induced oedema, which was significant after 2 and 3 weeks of treatment compared to the placebo group.