Necrosis or Related Skin Changes After Subcutaneous Injection of Buprenorphine Extended-Release: A Case Series

To describe eight cases of necrosis and related skin changes following a once-monthly subcutaneous buprenorphine extended-release (Bup-XR) injection, identify potential risk factors, and increase clinician awareness of this adverse drug reaction.

A retrospective case series of all patients reported to have necrosis or related skin changes after subcutaneous Bup-XR injection in one psychiatric hospital between February 1, 2023, and September 30, 2024. We collected demographic data, clinical characteristics, psychiatric and medical comorbidities, substance use patterns, treatment details (dose and injection site location), and outcomes. Descriptive statistics were used to summarize data.

Eight individual cases were identified (six males, mean age 41.25 years). Common symptoms reported by patients with this adverse drug reaction included pain (5/8 cases), erythema (4/8 cases), induration (2/8 cases), and edema (2/8 cases). Common clinical features were cocaine/crack-cocaine use (5/8 cases), nicotine use (6/8 cases), and anxiety or mood disorders (5/8 cases). The most frequent medical comorbidity was gastroesophageal reflux disease (3/8 cases). Two cases occurred from the same lot of Bup-XR injections supplied by the manufacturer.

We identified eight cases of necrosis or related skin changes in people who received subcutaneous Bup-XR injections. Clinicians, nurses, and pharmacists should be aware of this rare but potentially important adverse reaction when Bup-XR is prescribed. Clinical attributes common to more than half of the cases included male sex, middle age, cocaine/crack-cocaine usage, nicotine usage, and comorbid mood or anxiety disorders. Further research is required to establish whether these attributes are risk factors for adverse reactions of this kind.