[Duration of effectiveness of clonidine-depot: a double-blind trial (author's transl)].

Sixteen patients with chronic hypertension (grade I-II WHO classification) who had been successfully treated with clonidine (Catapresan Depot Perlongetten), received a placebo capsule on the second, third or fourth day of a five-day trial period. The placebo day was chosen at random. During the test period blood pressure and heart rate were measured daily once by the doctor and three times by the patient himself. There were no demonstrable changes in blood pressure or heart rate either on the placebo day or on the day after which exceeded the chance variations on the other three trial days. None of the patients had withdrawal symptoms.