Keywords: EM, erythema multiforme; HSV, herpes simplex virus; JAK-STAT, Janus kinase–signal transducer and activator of transcription; Janus kinase–signal transducer and activator of transcription; TRPS, tricho-rhino-phalangeal syndrome; chronic erythema multiforme; erythema multiforme; recurrent erythema multiforme; tofacitinib; tricho-rhino-phalangeal syndrome.