Abstract

An estimated 1.6 million Americans suffered from an opioid use disorder (OUD) in 2020. Effective OUD therapies are a public health priority. Buprenorphine, a partial agonist of the µ-receptor, is effective in supporting recovery from addiction. In 2017, the FDA approved once-monthly injectable buprenorphine (Sublocade) for patients suffering from moderate-to-severe OUD, to improve adherence. We report a case of a 31-year-old man with a history of OUD who received Sublocade injections for one year. Following his last injection in the abdomen (three weeks prior), he developed a 1.3 cm deep-seated ulcerated nodule with accompanying yellowish crust and erythematous border at the injection site. The lesion was excised and histologic sections showed skin with loose, granular, and palely eosinophilic foreign material intercalated into surrounding dermal collagen with a robust associated granulomatous foreign body reaction. An iron stain highlighted abundant hemosiderin-laden macrophages. We hypothesize that the foreign material represents infiltration of precipitated buprenorphine, as the only other ingredients in Sublocade are a biodegradable polymer and biocompatible solvent. Several reports have described foreign body deposition and ulceration in the setting of illicit injection of crushed buprenorphine tablets (“skin popping”), which were universally attributed to crospovidone deposition (an inert insoluble disintegrant found in pharmaceutical tablets). This is the first reported case, to our knowledge, of an approved injectable buprenorphine treatment causing a severe foreign body reaction, leading to significant ulceration necessitating surgical excision. The patient made a full recovery following excision. This case reveals a rare severe cutaneous adverse effect of Sublocade injection and highlights histologic features to be aware of among individuals treated with injectable buprenorphine, a population likely to grow as countries grapple with the opioid crisis.

Financial Disclosure:
No current or relevant financial relationships exist.