Eczematous dermatitis due to subcutaneous teriparatide injection

Teriparatide, or recombinant human parathyroid hormone, is approved for the treatment of osteoporosis. Possible cutaneous adverse events of teriparatide are urticaria, injection site pain, swelling, bruising, and pruritus. However, there have been no reports of widespread eczematous reactions caused by teriparatide. A 47-year-old male was recently diagnosed with osteogenesis imperfecta and prior to teeth extractions, he was subcutaneously injected with teriparatide. The patient developed multiple pruritic erythematous papules and plaques on his abdomen, around the site of the injection. A skin biopsy was done, which showed mild spongiosis and superficial perivenular lymphocytic infiltration with a few eosinophils. Drug-related eczematous changes were most likely suspected and in addition to the discontinuation of the injection, topical steroid was prescribed, in which dramatic improvements were observed. We report the eczematous hypersensitivity reaction caused by teriparatide, which is an adverse reaction that has not been reported before.