Use of gabapentin in the treatment of behavioural and psychological symptoms of dementia - A review of the evidence

Behavioural and psychological symptoms of dementia (BPSD) have been defined as a heterogeneous range of psychological reactions, psychiatric symptoms and behaviours that may be unsafe, disruptive and impair the care of a patient in a given environment. To date, there are no US FDA-approved drugs or clear standards of pharmacological care for the treatment of BPSD. The novel antiepileptic agent gabapentin is being increasingly considered for use in the geriatric population because of its relatively favourable safety profile compared with other classes of psychiatric medications. Gabapentin has been administered to several geriatric patients with bipolar disorder and patients with dementia. It has also been reported to be successful in the treatment of a 13-year-old boy with behavioural dyscontrol, a finding that suggested a possible role for gabapentin in the treatment of other behavioural disorders. The purpose of this review was to find evidence for the use of gabapentin in the treatment of BPSD. To this end, a search was performed for case reports, case series, controlled trials and reviews of gabapentin in the treatment of this condition. The key words 'dementia', 'Alzheimer's disease' and 'gabapentin' were used. Searches were performed in PubMed, PsycINFO, Ovid MEDLINE, Cochrane Library and ClinicalTrials.gov. The search revealed that there are limited data on the efficacy of gabapentin for BPSD in the form of 11 case reports, 3 case series and 1 retrospective chart review; no controlled studies appear to have been published to date on this topic. In most of the reviewed cases, gabapentin was reported to be a well tolerated and effective treatment for BPSD. However, two case reports in which gabapentin was used in the context of agitation in dementia with Lewy bodies questioned the appropriateness of gabapentin for all types of dementia-related agitation. The dearth of available data limits support for the off-label use of gabapentin for the treatment of BPSD. Furthermore, controlled studies should be conducted before gabapentin can be clinically indicated for the successful treatment of BPSD.