Inhibition of lactation by cyclofenil and bromocriptine

Summary. In a double blind controlled study of the inhibition of lactation 13 women received 300 mg of cyclofenil and 11 women 2.5 mg of bromocriptine twice daily for 14 days. Lactation was effectively inhibited by both drugs, but with bromocriptine there was a significantly higher frequency of relapse. The plasma concentration of prolactin, which decreased rapidly with bromocriptine, returned to the pretreatment level the day after drug treatment stopped, but with cyclofenil it remained low. Plasma oestradiol followed a similar pattern. Plasma FSH increased more rapidly with bromocriptine than with cyclofenil. There was no significant difference between the treatment groups at any stage for haematology, coagulation or liver function tests. The more sustained effect of cyclofenil on prolactin secretion with a reduced frequency of relapse, and the lower oestradiol level, which might indicate a reduced risk of thromboembolism, suggest that this drug has some advantage over bromocriptine in the inhibition of postpartum lactation.