*3.4.4 Granulomatous drug reactions*

Granulomatous drug reactions include four major types: interstitial granulomatous drug reaction, drug-induced accelerated rheumatoid nodulosis, drug-induced granuloma annulare, and drug-induced sarcoidosis [155].

The most common cutaneous features of interstitial granulomatous drug reaction are symptomatic erythematous plaques and papules with a predilection for the flexures (intertriginous areas, medial thighs, and inner aspects of the arms) [117]. Trunks also may be involved [117]. Sharply demarcated symmetrical annular erythematous lesions [155] are also described. Lesions may be generalized [117]. Interstitial granulomatous drug reaction completely regresses with drug cessation [155]. Other drug-induced granulomatous disorders are drug-induced accelerated rheumatoid nodulosis, with development of tender subcutaneous lesions during treatment with methotrexate, and drug-induced granuloma annulare (GA), mainly generalized, developed with paroxetine and drug-induced sarcoidosis [156]. Druginduced lesions are similar to the original lesions.
