Evolving and expanding scope of lupus-inducing drugs

Drug-induced lupus (DIL) is a side effect of long-term treatment with various medications, an idiosyncratic adverse drug reaction (ADR) that has been documented for some seven decades. While symptoms can be severe, DIL, unlike systemic lupus erythematosus (SLE), is fully reversible simply by discontinuation of the inducing medication, although full recovery can take several months. However, as with SLE, diagnosis of DIL is often missed or delayed in part because onset of symptoms can be gradual and variable and because the temporal link to the implicated drug is often not apparent. DIL typically develops after many months or years of largely symptom-free continuous drug use. While bonafide SLE or other idiopathic autoimmune disease would naturally be included in the differential diagnosis of someone who develops lupus-like symptoms, awareness that symptoms could be iatrogenic due to chronic medication can be the most important factor in making a correct and prompt diagnosis. Failure to do this often results in prolonged and worsening symptoms and unnecessary or ineffective anti-inflammatory/immunosuppressive treatment. The literature is replete with well-documented case reports of DIL due to some 70 different drugs as well as numerous reviews on this subject that list reported lupus-inducing drugs and their relative risk of causing this adverse side effect. However, because many drugs have a low or very low risk of causing lupus-like symptoms, it can be challenging to recognise DIL as the underlying cause of symptom development. In addition, increased use of new medications and/or the absence of publications of full case reports raise the possibility that other drugs exist with a DIL propensity. Gratefully, with the creation of VigiBase by the WHO in 1967,1 a mechanism for reporting potential lupus-inducing drugs has been facilitated without the formality of fully documented case reports. This Individual Case Safety Reports (ICSR) database now …