Two cases of myoclonus following administration of gabapentin for neuropathic pain in the end stage of malignancy
10.2512/jspm.5.308
- VernacularTitle:神経障害性疼痛に対しガバペンチン投与後に発症した，終末期がん患者におけるミオクローヌスの２例
- Author:
Hideyuki Honma
;
Satoshi Chihara
;
Rie Yamada
- Publication Type:Journal Article
- Keywords:
gabapentin;
myoclonus;
terminal stage
- From:Palliative Care Research
2010;5(1):308-313
- CountryJapan
- Language:Japanese
-
Abstract:
We report two cases of myoclonus following the administration of gabapentin for neuropathic pain in the end stage of malignancy. Patient 1: A septuagenarian woman with sarcoma of the uterus was admitted to our hospice. She complained of severe neuropathic pain in her left leg caused by an invasive lumbar tumor. To reduce the neuropathic pain, she was administered 200mg of gabapentin daily. Four months later, the gabapentin was increased to 400mg daily due to worsening pain in her left leg. Three days later, she felt muscle weakness in her left arm and frequent muscle twitches were observed even during sleeping. Myoclonus associated with gabapentin administration was suspected. The myoclonus disappeared after cessation of gabapentin for 2 days. Patient 2: An octogenarian man with renal cell carcinoma was admitted to our hospice. He was administered 200mg of gabapentin daily to reduce the neuropathic pain felt in his back and bilateral leg due to a metastatic tumor of a para-aortic lesion. On the next day, frequent muscle twitches were observed in his extremities and upper trunk while he was sleeping. Myoclonus associated with gabapentin administration was suspected, which disappeared within one day following cessation of the drug. Myoclonus is a rare side effect of gabapentin, but it may occur even with the low-doses given to patients with end-stage malignancy. Although the pathogenic mechanism of induction of myoclonus by gabapentin was suspected to be heterogeneous, discontinuation of gabapentin should lead to rapid resolution of symptoms. Palliat Care Res 2010; 5(1): 308-313
