Gabapentin add-on therapy for patients with spinal cord injury associated neurogenic overactive detrusors that are unresponsive to combined anticholinergic and beta-3 adrenergic therapy

Spinal cord injury is a major cause of lifelong morbidity and functional micturition problems. Some patients are refractory to the available therapeutics, even when used in combination. In this paper we report our results of using gabapentin as an add-on treatment in refractory overactive detrusor cases secondary to spinal cord injury. A total of 27 patients who had a spinal cord injury between the levels of the second thoracic and fourth lumbar vertebrae and had an overactive detrusor in urodynamic studies were included in this retrospective study. The patients were selected due to the fact that they also had not responded to a combination of an anticholinergic and mirabegron and had neuropathic pain. Gabapentin treatment was added to the previous therapy. Demographics, previous treatments, chronic conditions, urodynamic findings, clinical and urodynamic responses are reported in this paper. We observed a response to treatment in the urodynamic studies of 11 patients (40.17%), in terms of decreased detrusor contractions, maximal detrusor pressure, and the number of incontinence episodes. Sixteen patients did not respond to the gabapentin add-on therapy and were referred for Botulinum toxin injections to the bladder. Gabapentin add-on therapy can be considered as a third or further option, before Botulinum toxin injection, for patients with neurogenic overactive detrusor who did not respond to the combination of anticholinergics and mirabegron. The approved usage of gabapentin for neurogenic pain justifies its usage in this area. In our selected patient group, who had not responded to the combination therapy, we observed a clinical benefit in one-third of the patients.