title: Donepezil, an Acetylcholinesterase Inhibitor, Can Attenuate Gabapentinoid-Induced Somnolence in Patients with Neuropathic Pain: A Retrospective Chart Review.
abstract: Donepezil, an oral acetylcholinesterase inhibitor, is used to treat Alzheimer's disease and reportedly attenuates opioid-induced sedation in patients with cancer pain. Neuropathic pain is often treated with gabapentinoids (pregabalin, gabapentin), but gabapentinoid-induced somnolence sometimes prevents patients from using these agents. We conducted a retrospective chart review of patients with neuropathic pain to examine whether donepezil is useful for gabapentinoid-induced somnolence. We investigated pain severity in 13 patients before and after taking gabapentinoids and donepezil, the degree of gabapentinoid-induced somnolence before and after starting donepezil, and gabapentinoid dose escalation after taking donepezil. Donepezil was started at 3-5 mg/day upon experiencing gabapentinoid-induced somnolence. Likert-scale scores for somnolence (0 = no somnolence; 4 = severe somnolence with stumbling) improved significantly after starting donepezil (before: 2.3 ± 0.9, after: 0.5 ± 0.7; Wilcoxon's signed-rank test, P < .05), resulting in gabapentinoid dose escalation (before: 796.2 ± 564.3 mg, after: 1409.6 ± 526.9 mg; P < .05), which significantly decreased pain intensity (before: 7.4 ± 1.2, after: 5.0 ± 1.3; P < .05). Donepezil could be an alternative to psychostimulants for gabapentinoid-induced somnolence. The analgesic effect of gabapentinoids remained uncompromised by donepezil, which could enhance the dose-dependent analgesic effect of gabapentinoids.
authors.forename: Takamichi
authors.initials: T
authors.lastname: Kogure
authors.forename: Masahiko
authors.initials: M
authors.lastname: Sumitani
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Ikegami
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Abe
authors.forename: Jun
authors.initials: J
authors.lastname: Hozumi
authors.forename: Reo
authors.initials: R
authors.lastname: Inoue
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kawahara
authors.forename: Yoshitsugu
authors.initials: Y
authors.lastname: Yamada
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000588:Amines / Q000009:adverse effects*; D002800:Cholinesterase Inhibitors / Q000627:therapeutic use; D003509:Cyclohexanecarboxylic Acids / Q000009:adverse effects*; D006970:Disorders of Excessive Somnolence / Q000139:chemically induced / Q000150:complications* / Q000188:drug therapy*; D000077265:Donepezil; D005260:Female; D000077206:Gabapentin; D006801:Humans; D007189:Indans / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000150:complications* / Q000188:drug therapy; D010147:Pain Measurement; D010880:Piperidines / Q000627:therapeutic use*; D000069583:Pregabalin / Q000009:adverse effects*; D012189:Retrospective Studies; D005680:gamma-Aminobutyric Acid / Q000009:adverse effects*
chemical_list: D000588:Amines; D002800:Cholinesterase Inhibitors; D003509:Cyclohexanecarboxylic Acids; D007189:Indans; D010880:Piperidines; D000069583:Pregabalin; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin; D000077265:Donepezil
keywords: acetylcholinesterase inhibitor; donepezil; gabapentin; gabapentinoid-induced somnolence; neuropathic pain; pregabalin