Oral thyrotropin-releasing hormone treatment in inherited ataxias.

We studied the effectiveness of orally administered thyrotropin-releasing hormone (TRH) (40 mg/day) for 10 days against placebo in 11 patients with hereditary ataxias (HA). All patients completed the trial and none reported any noticeable side effects. A clinical rating scale for inherited ataxias and the Northwestern University Disability Scale for clinical disability showed no significant variation over the duration of the study. Manual dexterity, studied with the peg board test, showed a significant improvement after TRH compared with basal values, which persisted after washout. Eye movement alterations, as revealed by electroculography were reduced after TRH and washout when compared with placebo and basal scores. Hormonal monitoring showed only a transitory effect on the hypothalamus-hypophysis-thyroid axis. These results demonstrate that orally administered TRH has a mild but significant effect only on some cerebellar symptoms in HA.