Myoclonus as a presentation of opioid-induced neurotoxicity

Mioclonías como presentación de neurotoxicidad inducida por opioides

Introduction: opioid- induced neurotoxicity (OIN) can manifest as myoclonus, a rare complication requiring early intervention. Objectives: to report a rare side effect of opioid therapy and identify the underlying risk factors. Case Report:  A 78-year-old woman coming from southwest Colombia, diagnosed with breast and thyroid cancer with lung metastasis. She presented with chronic neck pain secondary to cervical surgical lymphadenectomy, inadequately treated with a two opioids combination (hydrocodone-oxycodone). Following opioid therapy instauration, she presented myoclonic contractions of the upper extremities. During care provision, she underwent various studies, which were within the normal range. It was concluded that this was a case of opioid-induced neurotoxicity. Pharmacological management was reviewed. One of the opioids was discontinued and the dosage of the other opioid was adjusted, with favorable clinical outcomes. Conclusions: assessing risk factors and appropriate use of opioid medication favor patient pharmacological safety. Early identification of symptoms warrants a successful intervention and symptom control.

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