Low-dose oral clonidine. A simple and reliable growth hormone screening test for children

Abstract

We evaluated the efficacy and side effects of a low dose of oral clonidine hydrochloride on growth hormone release in 24 healthy short children; ten received 100 micrograms (group A) and 14 received 50 micrograms (group B). The mean +/- SD growth hormone peak at 60 minutes was 14.5 +/- 6.3 mg/mL in group A v 11.6 +/- 6.1 mg/mL in group B. Failure rate (growth hormone less than 10 mg/mL) was 10% in group A and 36% in group B. The drop in cortisol levels was similar in both groups. Blood pressure did not change significantly, and only mild somnolence was noted in all. A single dose of oral clonidine hydrochloride approximating 100 micrograms/sq m, followed by one blood sample after 60 minutes seems to be an effective and safe screening test for growth hormone deficiency in short children.