The action of etilefrin (Effortil Depot Perlongets) was compared with placebo in a double-blind study in 24 female geriatric patients with sympathicotonic orthostatic hypotension. After determining the basic values, all patients were treated with the active substance in a titration phase lasting one week (dosage 2-3 Perlongets/day). The decrease in systolic blood pressure and the increase in pulse rate while standing were then statistically significant lower (p less than (p less than 0.001) when compared with the basic values. In 17 out of 21 cases of collapse which occured while standing before therapy was commenced no further collapse occurred (p less than 0.005). Following the titration phase treatment with etilefrin was continued in 12 patients in a double-blind study while the remaining 12 patients were changed over to placebo as a withdrawal study. The effect continued in those patients treated with the active ingredient and the average values and incidence of effects improved further. On the other hand, in the placebo group there was one again a marked decrease in systolic blood pressure and increase in pulse rate as observed in the basic values. The symptomatology, particulary episodes of collapse increased again. There was a statistically significant difference between the action of etilefrin and placebo for all criteria (both objective and subjective parameters). Side-effects were not observed.