Possible mechanisms of action of antimalarials in rheumatic disease.

Understanding of the mechanism of action of the antimalarials in rheumatoid arthritis remains limited in spite of knowledge of a wide range of potentially relevant effects at the cellular level. Among the difficulties with proposed mechanisms of action are a lack of specificity, doubt about demonstrable effects at appropriate concentrations and a failure to explain the slow onset of action. It is possible that pharmacokinetic factors, or the slow change in the underlying disease pathology, might account for the slow onset.