A double‐blind clinical trial of isoniazid in Huntington disease

Publisher Website
Google Scholar
Abstract
Isoniazid (INH) was given to 9 patients with Huntington''s disease (HD) in a double-blind, placebo-controlled crossover trial. In an earlier open trial, 3 of 6 patients had improved, and 1 of them remained improved after 7 yr on INH. Only 1 patient benefited in the present trial. All patients excreted small amounts of hydrazine in their urine while taking INH, and it is this INH metabolite that elevates GABA content in brain. GABA concentrations were markedly increased in CSF during INH therapy. Lack of clinical improvement in most HD patients despite elevation of brain GABA content suggests that in the minority who are benefited, INH may be acting by some mechanism other than increase of GABAergic neuronal function.