Treatment of rheumatoid arthritis with levamisole: long-term results and immune changes.

We treated 29 rheumatoid arthritis patients with levamisole. on the basis of a 25% improvement in any 3 of 6 measurements 95% of the patients had a favourable response within 20 weeks. However, 64% of the patients discontinued levamisole by 40 to 60 weeks because of rash or secondary treatment failures. Delayed skin reactivity to streptokinase-streptodornase increased significantly in the entire treatment group, but there was in inverse correlation between skin test enhancement and clinical response. There was no overall change in lymphocytes response to phytohaemagglutinin (PHA) after 4 and 16 weeks of treatment, but seven patients with enhanced lymphocyte responsiveness to PHA experienced an earlier clinical response to levamisole. Treatment with levamisole frequently results in clinical improvement in rheumatoid arthritis, but this is not clearly related to a stimulatory effect on cell-mediated immunity. Its long-term usefulness may be limited by a high incidence of relapse and rash.