Abstract Taking into account the toxicology of soluble barium salts, the authors treated 32 hypertensive subjects who were confirned to bed in two old people's homes with Baryta carbonica 15 CH versus placebo in a randomized double-blind study. Seventeen patients were given Baryta carbonica and 15 placebo. Taking the groups as a whole, no statistically significant differences were found between the effects of placebo and active drug on the blood pressure. But the four subjects who had been prospectively considered sensitive and were treated with Baryta carbonica gave strongly positive results. Some interesting conclusions were arrived at both from the general medical and the homœopathic point of view.