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Atypical myopathy: pentazocine induced
Murali K Kolikonda1, Suneela Cherlopalle1, Manasa Enja1
1Drs. Kolikonda, Cherlopalle, Enja, and Lippmann are with the University of Louisville School of Medicine, Department of Psychiatry, Louisville, Kentucky.
Innovations in Clinical Neuroscience
|May 23, 2015
Summary
Pentazocine, an opioid analgesic, can cause rare iatrogenic myopathy with muscle fibrosis after intramuscular injections. Clinicians should recognize this side effect and avoid repeated injections to prevent muscle damage.
Area of Science:
- Neurology
- Pharmacology
- Pathology
Background:
- Pentazocine is a mixed agonist/antagonist opioid analgesic.
- Intramuscular administration of pentazocine can lead to iatrogenic myopathy.
- This myopathy is characterized by fibrosis and is a rare but significant side effect.
Purpose of the Study:
- To describe a case of pentazocine-induced myopathy.
- To highlight the clinical presentation and pathological features.
- To alert clinicians to this potential adverse drug reaction.
Main Methods:
- Case report of a 42-year-old male patient.
- Clinical examination and assessment of muscle symptoms.
- Review of literature on pentazocine-induced myopathy.
Main Results:
- The patient presented with bilateral gluteal muscle wasting.
- He also experienced leg stiffness and woody induration.
- The myopathy was attributed to repeated intramuscular pentazocine injections.
Conclusions:
- Pentazocine-induced myopathy is a rare iatrogenic condition.
- Fibrosis is a key pathological feature.
- Clinicians must be aware of this potential side effect and avoid repeated intramuscular pentazocine administration.
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