Frequency and type of reactions to antituberculosis drugs: Observations in routine treatment

Setting: United Kingdom, 1978-1992. Objective: To assess the incidence and type of reactions to antituberculosis drugs in an unselected series of patients. Design: All patients treated for tuberculosis had details of drug treatment, durations and side-effects requiring alteration of treatment available. The data was compiled retrospectively for 1978-1980 patients and prospectively thereafter. Analysis of drug reactions was by drug, total months drug use, by age, sex and ethnic group, and reaction type. Results: Of 1317 patients 67 (5.1%) had 70 reactions to antituberculosis drugs requiring modification of treatment. The frequency of drug reactions increased from 2.3% at age 0-19 to 4.6% at age 20-39, 7.1% for age 40-59 and to 8.4% for those aged 60 and over. Females had significantly higher reactions rates than males. White patients had higher reaction rates than Pakistani and Indian patients, mainly due to the average age being greater. Conclusion: The drug reaction rate of 5.1% in this largely prospective study is lower than that reported in other unselected series in the UK and other countries.