Hypocalcemic effects of rectal and intramuscular administration of synthetic salmon calcitonin.

To assess the acute biological activity of a new rectal form of synthetic salmon calcitonin (SMC), 10 healthy subjects were randomly assigned, according to a crossover design, to single doses of either 50 IU SMC intramuscularly or 100 IU SMC rectally. Ionized and total calcium were measured as SMC bioactivity indicators in blood samples collected during a 6-hour period after the administration of the drug. In all the subjects, rectal administration of 100 IU of SMC induced falls in both plasma total calcium and whole blood ionized calcium: similar levels were observed after intramuscular injection of 50 IU of SMC. The pharmacodynamic bioavailabilities for total and ionized calcium of the 100 IU suppository and the 50 IU intramuscularly were 106% and 60%. The total and ionized calcium AUCs were the same after i.m. injection and suppository. We conclude that, in normal subjects, synthetic salmon calcitonin administered by the rectal route at the dose of 100 IU is effective and has the same biological effects as 50 IU of SMC given intramuscularly. Therefore, this new rectal form may be a useful alternative to parenteral injection.

New perspectives in medical management of hyperprolactinemia.

We performed 113 new treatments in 98 patients (pts) (69 females and 27 males), 41 with macroprolactinoma, 26 with microprolactinoma, 5 with empty sella and 26 with idiopathic hyperprolactinemia. Parlodel LA was administered in 31/113, Parlodel LAR in 51/113, Parlodel SRO in 24/113 and Cabergoline in 8/113. In each pt the clinical effect, PRL plasma level CT-scan and visual field examination were monitored. PRL plasma levels normalized in 84/98 pts. In 13/41 macroadenoma pts a complete disappearance of the adenomatous mass was observed at CT-scan after 0.5-3 years' oral bromocriptine or Parlodel LAR therapy. The clinical features normalized in most of the pts. In conclusion, the new long acting dopamine agonists may represent the future of the management of hyperprolactinemic states because of their effectiveness, tolerability and good compliance.