Myofibrosis in a pentazocine addict

Abstract

Pentazocine, a synthetic narcotic analgesic, is commonly used for the relief of moderate to severe pain, but has been rarely abused also. It is usually well tolerated; however, adverse effects are not uncommon, when higher doses are used, especially in a dependent fashion. There are reports of various complications associated with its use, including skin fibrosis, skin ulceration, abnormal skin pigmentation and symmetrical myopathy with fibrous myopathy. Fibrosis has usually been reported in the muscles at the site of injection of the drug. Being opioid in nature, it has a high abuse potential. We report a case of pentazocine-induced myofibrosis in a 33-year-old man involving muscles which were not injected with pentazocine. This case highlights the care that needs to be taken when prescribing opioid analgesics, such as pentazocine, as routine painkillers. Rare consequences such as myofibrosis are devastating and can cause significant lifelong disability.

Keywords

• Addiction
• myofibrosis
• pentazocine