Pattern and Severity of Adverse Drug Reactions Associated with AntitubercularTherapy

Abstract

Background: Adverse drug reactions (ADRs) associated with antitubercular therapy (ATT) remain a major
challenge in tuberculosis (TB) management, particularly in developing countries such as India, where the TB
burden is high. ADRs may adversely affect treatment adherence, increase treatment interruption, and contribute
to treatment failure and drug resistance. Objective: The objective of the study was to assess the pattern, severity,
causality, and suspected drugs associated with ADRs among TB patients receiving ATT at a district hospital.
Materials and Methods: A prospective observational study was conducted among 124 TB patients receiving ATT
at a district hospital in Madanapalle, Andhra Pradesh. Patient demographic details, clinical characteristics, treatment
regimens, and ADRs were recorded using a structured data collection form. Causality assessment was performed
using the World Health Organization-Uppsala Monitoring Centre (WHO-UMC) scale, while severity assessment was
performed using the Hartwig and Siegel severity scale. Data were analyzed using descriptive statistics and expressed
as frequencies and percentages. Results: Among the study participants, 52.4% were males, and pulmonary TB
accounted for 69.35% of cases. The most frequently reported ADRs were nausea, vomiting, and gastritis (16.93%),
peripheral neuropathy (15.32%), skin rashes (15.32%), and hepatotoxicity (14.51%). Neurological ADRs constituted
the most commonly affected organ system (22.58%). Most ADRs were categorized as probable according to the WHO-
UMC assessment (64.51%), while mild and moderate reactions each accounted for 38.7% of cases. Pyrazinamide
and isoniazid were the most commonly implicated drugs. Inferential analysis demonstrated a significant association
between second-line ATT and severe ADRs (P = 0.001), as well as neurological ADRs (P = 0.024). Conclusion: ADRs
associated with ATT are common and frequently inv olve the neurological and gastrointestinal systems. Second-line TT was significantly associated with severe and neurological ADRs, highlighting the need
for intensive pharmacovigilance, early ADR
detection, and close clinical monitoring during
TB treatment.