Endocrine Abstracts

*These authors contributed equally to this work

Introduction

The prevalence of obesity has risen dramatically worldwide in the last three decades. Due to this obesity pandemic, a growing demand for weight-loss drugs has emerged. The increased use of these drugs has consequently lead to an increase in the report of adverse reactions.

Case report

A 45-year-old woman with past medical history of class I obesity and psoriatic arthritis, presented with an itchy rash, developing one day after starting a weight-loss drug, naltrexone/bupropion. Physical examination revealed an erythematous maculopapular rash on the trunk and upper limbs, without mucosa involvement. Seeing as a drug reaction was suspected, naltrexone/bupropion was discontinued and prednisolone 0.5 mg/kg/day was initiated. Two days later, the rash progressed to form multiple, non-follicular, pinhead-sized pustules, on an edematous disseminated erythema, extending to the face and lower limbs. The patient was admitted to the hospital, and cyclosporine 3 mg/kg/day and prednisolone 0.5 mg/kg/day were administered, with good response. Nevertheless, cyclosporine had to be suspended after one week due to hepatotoxicity. Histological assessment of a skin biopsy was consistent with pustular psoriasis. After two weeks, the patient was discharged with a slow tapering plan of prednisolone. She later relapsed with classic psoriatic plaques, occasionally studded with pustules, on the limbs. Treatment with adalimumab was subsequently initiated. Patch tests were performed on the upper back six months later with naltrexone/bupropion, naltrexone, and bupropion (each 30% pet.). Readings on day (D) 3 showed positive reactions to naltrexone/bupropion and bupropion. A biopsy of this reaction confirmed an allergic dermatitis.

Conclusion

Psoriasis can be triggered or exacerbated up by certain drugs. Several cases of severe bupropion-associated skin drug reactions and psoriasis have been reported, including one case of psoriasis related to the anti-obesity drug naltrexone/bupropion. Nonetheless, the exact mechanism by which bupropion triggers psoriasis is unknown. In our case, the positive patch test to bupropion suggests that an initial acute generalized exanthematous pustulosis caused by bupropion might have elicited psoriasis as a result of the Koebner phenomenon. To the best of our knowledge, this is the first report on a type IV hypersensitivity reaction to bupropion documented through patch testing. There is a known association between psoriasis and metabolic syndrome, a frequent diagnosis in obese patients. Hence, special precautions should be taken when prescribing naltrexone/bupropion to patients with a known history of psoriasis.