[Comparison of plasma concentration and tolerance of a single dose of human calcitonin by intradermal and subcutaneous administration]

Abstract

The aim of the study was to compare plasmatic levels of calcitonin obtained after intradermic (ID) and usual subcutaneous (SC) route of administration.

Method: 6 volunteers between 18 and 40 years old received calcitonin 0.5 mg (Cibacalcin, Ciba-Geigy Laboratory) by ID and SC routes in a random order but at the same site of injection. Each administration was spaced by 8 days. Plasmatic levels were measured by R.I.A. before administration then 2 (M2), 7 (M7), 15 (M15), 30 (M30) minutes and 1 (H1), 2 (H2), 4 (H4), 8 (H8), 12 (H12) hours after each administration.

Results: Tmax were at 23.6 +/- 10 min and 16.2 +/- 7.5 min for SC and ID routes respectively. With ID route, Tmax was reached simultaneously or earlier (3 times). Cmax is significantly higher with ID route. Neither mean plasmatic levels at each plasmatic dosage nor mean areas under the curve between 0 to 1,440 min or between 0 to 480 min (this latest AUC calculate to minimize the importance of calcitonin basal level) were significantly different with ID and SC routes. 16 mild side effects (8 with each administration) were observed in 4 subjects. They appeared before 5 min. and were transient (1 hour) for cutaneous manifestations, and later between hours 3 and 7 for nausea and vomiting or asthenia. The mean lowering of calcemia was 0.29 +/- 0.21 and 0.18 +/- 0.11 mmol/l respectively for SC and ID route. In this study ID and SC routes for calcitonin administration are not different with regard to plasma levels and side effects.