Misleading T3‐test Values in Psychiatric Patients Treated with Orphenadrine

Publisher Website
Google Scholar
Abstract
Thyroid laboratory tests were assessed in 74 psychiatric patients without clinical evidence of overt thyroid disorder. In a first screening of 42 patients, 13 were found to have elevated levels of triiodothyronine uptake test (T3-test) by a Sephadex method. Ten of these patients also had an elevated free thyroxine index (fT.DELTA. index). Of the 13 patients with increased T3-test values, 10 were on orphenadrine (Disipal) treatment or had recently stopped taking the drug. In a second study, thyroid function tests were compared in 15 pairs of matched psychiatric patients treated with orphenadrine or other anticholinergic drug. Values of T3-test and free thyroxine index were significantly higher among patients treated with orphenadrine. Finally, orphenadrine was instituted in four patients and withdrawn in six patients. T3-test values and free thyroxine indices increased gradually after orphenadrine treatment had been initiated and decreased gradually when it was withdrawn.

This publication has 5 references indexed in Scilit: