Fenoterol depot and fenoterol in premature uterine contractions--a multicentric double-blind comparative study.

In a double-blind randomized study, the effect of a single dose of a fenoterol preparation with delayed release of active substance (designated as fenoterol depot) was compared with a fenoterol product with undelayed release of active substance (designated as fenoterol) in two groups respectively comprising 66 and 65 female patients with premature uterine contractions. The fenoterol depot was administered p.o. in a single total dose of 21 mg at the beginning of an investigation period of 360 minutes and the fenoterol was administered p.o. within 235 minutes in three identical consecutive doses resulting in a total dose of 22.5 mg. The increased uterine activity present at the beginning was markedly lowered by an initial intravenous infusion of Partusisten. After administration of the two oral preparations, the uterine contractions remained at the low level achieved. The fenoterol depot was slightly superior to fenoterol with regard to the reduction of the duration of contractions: the difference in the inhibition of the duration of the contraction between the two preparations was a maximum of 25.7% in favor of fenoterol depot. The frequency of uterine contraction was substantially reduced by both preparations, but to a greater extent by the depot form. The tocolytic efficacy and the tolerance were rated as "good" in 70% and 75% respectively with fenoterol depot and in 69% and in 71% respectively in the case of fenoterol. The maternal pulse rate remained at the level reached at the end of Partusisten infusion with the two preparation, and the blood pressure fluctuated slightly within the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)