Adverse drug reactions in tuberculosis and management

Abstract

Background: Treatment of drug susceptible tuberculosis (DS-TB) requires regimens containing first line drugs (FLDs') whereas drug resistant tuberculosis (DR-TB) are treated with regimens comprising combination of both second line drugs (SLDs') and few FLDs'. Adverse drug reactions (ADRs') to these anti-tubercular drugs are quite common as they are being used for longer duration. ADRs' may cause associated morbidity and even mortality if not recognized early. There are major concerns regarding treatment of DR-TB patients particularly with SLDs' in that they are expensive, have low efficacy and more toxic as compared to FLDs'. There may be a severe impact on adherence and higher risk of default and treatment failure affecting outcome overall if such ADRs' are not properly managed.

Methods: A search strategy was adopted involving principal electronic databases (Pubmed, EMBASE, Google and Google scholar) of English language articles from 1990 till now, using various terms in combination. All articles with resulting titles, abstract and full text, when available were read and kept for reference.

Results: 101 articles including 4 systematic reviews have been identified. The overall prevalence of ADRs' with FLDs' and SLDs' are estimated to vary from 8.0% to 85% and 69% to 96% respectively. Most ADRs' are observed in the intensive phase as compared to continuation phase. No difference in frequency of ADRs' was reported with intermittent or daily intake of anti-tubercular drugs. The occurrence of ADRs' may be influenced by multiple factors and may range from mild gastrointestinal disturbances to serious hepatotoxicity, ototoxicity, nephrotoxicity peripheral neuropathy, cutaneous ADRs', etc. Most of ADRs' are minor and can be managed without discontinuation of treatment. Some ADRs' can be major or severe causing life-threatening experience leading to either modification or discontinuation of regimen and even mortality if not recognized and treated promptly.

Conclusion: Early recognition by active surveillance and appropriate management of these ADRs' might improve adherence and treatment success.

Keywords: Adverse drug reactions; Drug resistant; First line drugs; Second line drugs; Tuberculosis.