A double-blind clinical study on long-term use of oxyphenbutazone and tolfenamic acid in connection with telecobalt therapy.

Thirty-one patients who suffered from various cancers in the pelvic region were treated in a double-blind clinical long-term study either with placebo, N-(2-methyl-3-chlorophenyl)-anthranilic acid (tolfenamic acid, Clotam) or oxyphenbutazone in order to diminish the local reactions after telecobalt therapy. The results were difficult to judge and no clear differences were seen between the groups. The side-effects were slight and unspecific, except gastrointestinal distresses, which occurred with both tolfenamic acid and oxyphenbutazone, but were more severe with the latter. No significant changes were seen in the blood counts, liver or kidney function tests with tolfenamic acid. In the oxyphenbutazone group S-ALAT, S-AFOS and direct bilirubin were slightly elevated. Blood in feces was more frequent in the drug-treated than in the placebo group. In the light of the present and earlier studies tolfenamic acid appears to cause less side-effects than oxyphenbutazone in prolonged treatment.