GROWTH-HORMONE RESPONSE TO BACLOFEN - A COMPARISON OF 10-MG AND 20-MGDOSES IN HEALTHY-MEN

Growth hormone (GH) response and baclofen levels were measured in seve n healthy adult men following a 10-mg and a 20-mg dose of oral baclofe n (gamma-aminobutyric acid(B) agonist) to determine the preferred dose in baclofen challenge studies. Multivariate analysis of variance (ANO VA) with repeated measures revealed no differences between the doses, However, when a univariate ANOVA with repeated measures was performed for each dose, the 10-mg dose showed no significant GH response over t ime, whereas the 20-mg dose showed a significant GH response over time . The average Delta GH (change in GH from baseline) was 7.84 ng/ml (SD = 10.17) for the 10-mg dose and 3.34 ng/ml (SD = 3.64) for the 20-mg dose. The variability in the Delta GH response to the 10-mg dose was s ignificantly greater than the response to the 20-mg dose of baclofen. This variance in GH response was not explained by the differences in s erum baclofen levels. Thus, a 20-mg baclofen dose appears to be prefer able to a 10 mg-dose in baclofen challenge studies.