Penicillamine in the treatment of rheumatoid arthritis.

Between 1973 and 1979, 203 patients with classical or definite rheumatoid arthritis were treated with chloroquine phosphate, gold, or penicillamine. Of 132 receiving penicillamine, 76 received it as the sole treatment. Forty of 50 withdrawals from penicillamine were side effect-related, although 4 of these 50 subsequently resumed therapy. Nineteen showed no response to penicillamine. Eight-six remained on the drug in early 1980. Penicillamine compares favourably with gold with regard to clinical response, number of side effects, and withdrawal rate of the patients on penicillamine.