1Department of Oral Biology, Semmelweis University, Budapest, Hungary
2Department of Anatomy, Semmelweis University, Budapest, Hungary
Introduction: Postherpetic neuralgia (PHN) is the most common sequelae of herpes zoster infection caused by varicella-zoster virus (HZV). It is commonly found in elders – over 50 years and immunocompromised patients with a wide range of incidence. The treatment of PHN is to alleviate pain but the outcome is unfavourable. For PHN prevention multiple methods have been suggested, such as vaccination, corticosteroids, antiviral, anti-epileptic or antidepressant agents. However, their effectiveness is questionable and not well demonstrated.
Aims: To assess the effectiveness of gamma-aminobutyric acid (GABA) and derivatives used in preventing PHN.
Method: The electronic databases were searched on 26 February 2018 in PubMed, Web of Science, Ovid, Scopus and EMBASE. The PROSPERO was also searched for the ongoing and published meta-analysis. The articles gained from searching were included and excluded by selection criteria. All English randomized controlled clinical trials (RCTs) of GABA given within 72 hours after the onset of herpes zoster for preventing PHN are considered. Two authors independently selected trials, evaluated the risk of bias, and extracted and analysed data.
Results: Only two RCTs with a total of 149 participants were qualified; one trial evaluated pregabalin and another one evaluated gabapentin. There is another ongoing randomized, double-blind clinical trial with different doses of gabapentin. The presently available data are not enough to conduct meta-analysis. But these RCT studies both suggest that GABA is not effective in preventing PHN in the applied low dose-range. However, a recent uncontrolled trial, and also an ongoing RCT suggest that higher doses of GABA derivatives could be effective in such an application.
Conclusion: Low doses of GABA derivatives are not effective for preventing PHN. Further prospective well-designed RCTs are needed to show whether increasing the dose of such compounds turn out to be useful as treatment.
Doctoral School: Clincal Medicine
Program: Dental Research
Supervisor: Gábor Gerber and Gábor Varga
E-mail address: firstname.lastname@example.org