A Comparative Study between Vaginal and Rectal Routs of Bromocriptine Administration

To assess the efficacy and possible potential side effects of alternate routes of treatment, 2.5mg bromocriptine was administered vaginally or rectally to five normoprolactinemic and four idiopathic hyperprolactinemic women. Serum bromocriptine and prolactin (PRL) levels were measured hourly for the first 12 hours, then every 2 hours for the following 12 hours. The mean peak bromocriptine levels were 641.0 ± 200.1 pg/ml and 386.5 ± 134.8 pg/ml in the normoprolactinemic and hyperprolactinemic groups, respectively. Maximum PRL reduction rate was 67.7 ± 3.4% at 11.3 ± 1.1 hours and 44.8 ± 0.7% at 21.5 ± 1.5 hours after vaginal administration in the normoprolactinemic and hyperprolactinemic groups, respectively. In contrast, in the rectal treatment group the mean peak values of serum bromocriptine were 364 pg/ml and 314.5 ± 3.9 pg/ml in the normoprolactinemic and hyperprolactinemic groups, respectively. Maximum PRL reduction rate was 38.1% at 8 hours and 21.0 ± 10.4% at 17.0 ± 3.5 hours in the normoprolactinemic and hyperprolactinemic gryoups, respectively. In conclusion, we suggest that the vaginal route of administration is as effective and has fewer side effects than by the oral route. Furthermore, the rectal route is an alternate method of treatment for patients who cannot be administered bromocriptine by vaginal route