title: Biochemical and clinical effects of fenclofenac in thyrotoxicosis.
abstract: Administration of the anti-inflammatory drug fenclofenac (600 mg bd) for 28 days to four females with thyrotoxicosis resulted in a rapid decline in thyroid hormone levels. The mean total thyroxine (T4) level of 173 +/- 8.6 (SEM) nmol/l before therapy was normalized to 70 +/- 6.4 nmol/l after administration of the drug for 7 days. Free T4 levels also decreased significantly but not to within the reference range in all subjects. Mean total triiodothyronine (T3) and reverse T3 levels declined from 6.2 +/- 0.9 nmol/l and 0.63 +/- 0.2 nmol/l respectively before therapy to 3.8 +/- 0.5 nmol/l and 0.52 +/- 0.1 nmol/l after 7 days' treatment but remained consistently elevated in all subjects. Clinical thyroid status remained unchanged despite these marked reductions in circulating thyroid hormone levels, suggesting that fenclofenac was of no therapeutic benefit.
mesh_terms: D000328:Adult; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood / Q000188:drug therapy*; D008875:Middle Aged; D010648:Phenylacetates / Q000627:therapeutic use*; D013961:Thyroid Gland / Q000503:physiopathology*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D014285:Triiodothyronine, Reverse / Q000097:blood
chemical_list: D000893:Anti-Inflammatory Agents; D010648:Phenylacetates; D014284:Triiodothyronine; D014285:Triiodothyronine, Reverse; D013974:Thyroxine; C012970:fenclofenac