Abstract: | One hundred and forty-four courses of levamisole were given in various dosage schedules for the treatment of rheumatoid arthritis from 1976 to 1980. A placebo-controlled double-blinded study was analyzed traditionally and life table analysis used to describe events during follow-up. Lower dosage was significantly less toxic, but not significantly better than placebo. Toxicity to other slow acting anti-rheumatic drugs did not predispose to levamisole toxicity. Because effective doses are poorly tolerated, and tolerable lower doses are relatively ineffective, levamisole cannot be recommended as standard treatment of rheumatoid arthritis. |