Gabapentin for uremic pruritus in hemodialysis patients: a qualitative systematic review

PURPOSE OF THE REVIEW: Uremic pruritus (UP) is a common discomfort of dialysis-dependent end-stage renal disease. Some studies suggest a neuropathic cause of UP. Gabapentin, an anticonvulsant, has shown promising results as an emerging drug to treat this condition. OBJECTIVE: An updated qualitative systematic review was conducted to evaluate its efficacy and safety in hemodialysis patients. SOURCE OF INFORMATION: Ovid MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, and Google Scholar through June 2015 were used as sources of information. PATIENTS: Patients are adult hemodialysis patients receiving gabapentin for UP. METHODS: All randomized controlled trials (RCTs), quasi-RCTs, observational studies, open-label studies, and retrospective studies were included. Case series and case reports were excluded. All descriptions and data were extracted independently by two authors. RESULTS: Seven studies evaluating gabapentin with a total of 179 patients were included. Most patients were refractory to antihistamines and topical emollients. Statistically significant favorable outcomes on pruritus scores were found in six studies. Five studies evaluated antipruritic efficacy based on a 10-point visual analog scale (VAS), and improvements in the range of an absolute decrease of 5.7 to 9.4 points from baseline were achieved on average by 3–8 weeks of treatment. Side effects are common with six studies reporting at least 26 incidences of side effects such as somnolence, dizziness, and fatigue. A total of four patients reportedly discontinued gabapentin due to intolerability. LIMITATIONS: Our review is limited by the inclusion of generally small, lower quality studies that lacked comparator groups or were open-label studies. Since the first two randomized controlled trials were published, no further high-quality studies have been conducted. IMPLICATIONS: Our review supports a trial of gabapentin for the management of UP in hemodialysis patients refractory to antihistamines and/or emollients. The results should be interpreted cautiously due to the lower quality of included studies. We recommend a starting dose of 100 mg orally after hemodialysis to minimize adverse events in this population.