The antimalarials chloroquine and hydroxychloroquine have been used for the treatment of inflammatory diseases for more than 60 years. Even today new indications evolve due to the complex mode of action of these compounds. Due to the fear of side effects, especially irreversible retinopathy, their use is often limited. These side‐effects, however, are a consequence of excessive daily dosages. An effective, safe therapy needs correct dosing, i. e. adherence to maximal daily dosages of 3.5(–4) mg chloroquine or 6(–6.5) mg hydroxychloroquine per kilogram ideal body weight. If the actual body weight is lower than the ideal body weight, this actual weight is used for the calculation of the dosage. Observing these limits allows a rather safe therapy of the diseases like lupus erythematosus, REM syndrome, porphyria cutanea tarda (2 × 125 mg chloroquine/week), cutaneous sarcoidosis and dermatomyositis. If standard therapies fail, then antimalarials can be tried to treat Sjögren syndrome, granu‐loma annulare or erosive lichen planus. If therapy fails, either can be combined with quinacrine to increase their effectiveness. Chloroquine and hydroxychloroquine are indispensable and well‐tolerated essential drugs in dermatology and especially suited as part of a combination scheme, for example with corticosteroids, as they act synergistically and reduce side‐effects.
Use of antimalarials in dermatology