Multiple sclerosis and alopecia areata: drug-induced alopecia areata or coexisting autoimmune phenomena?

Alopecia areata (AA) is an inflammatory condition characterized by nonscarring alopecia, of which the pathogenesis has been hypothesized to be a multifactorial process involving genetic, environmental and autoimmune aspects. AA shares multiple gene loci and pathomechanisms with other autoimmune disorders, including multiple sclerosis (MS). Drug-induced AA is a concept that is underreported and poorly understood. Current MS-targeted treatments involve reconstitution of the immune system, with cases of AA being reported. However, translational work has shown novel MS treatments to be beneficial in treating AA and they are currently being trialled for this purpose. We outline the literature within this field to increase awareness and inform patients and clinicians.