Drug-induced antinuclear antibodies and lupus syndromes.

Drugs capable of triggering the onset of systemic lupus erythematosus may be divided into those that do so by pharmacological properties of their own and those that do so by eliciting allergic reactions which bring about lupus. Drugs in the first group vary in their potency to activate lupus. They all elicit antinuclear antibodies in the majority of patients who receive them but they only cause lupus in a small percentage of patients. This dichotomy suggests that a predisposition is required for the development of lupus upon intake of these drugs. The mechanism whereby these drugs elicit antinuclear antibodies seems to relate to coupling to and/or modification of, nuclear antigens. The patterns of antinuclear antibodies elicited by these drugs in individuals who receive them correlate well with their known reactivity with various nuclear antigens.