Myoclonus secondary to withdrawal from transdermal fentanyl: case report and literature review.

Myoclonus is a common and well-described adverse effect of opioids. Most cases reported in the literature have been associated with opioid administration, rather than with opioid withdrawal. We describe a case of myoclonus secondary to withdrawal from transdermal fentanyl. We review the literature regarding myoclonus related to opioid therapy (opioid-induced myoclonus) and withdrawal (opioid withdrawal myoclonus), and discuss possible mechanisms and therapies for these phenomena.