For latent TB infection, what is the standard preventive regimen duration with isoniazid?

For latent TB infection, what is the standard preventive regimen duration with isoniazid?

• A. Rifampin for 6 months
• B. Isoniazid for 9 months
• C. Rifapentine-based weekly 12 weeks
• D. Ethambutol for 12 months

Answer: (B)

Treating latent TB infection aims to prevent progression to active tuberculosis by eradicating dormant bacilli, and the duration of drug therapy with isoniazid influences how well this protection lasts. The traditional and standard regimen with isoniazid is nine months of daily therapy, which provides strong protection against reactivation while maintaining manageable safety and adherence for most patients. There are shorter or alternative regimens, such as rifampin-based or rifapentine-based courses, but those are not isoniazid-only regimens. Ethambutol is not used for latent TB infection. So the duration that best fits the question for isoniazid preventive therapy is nine months.

Treating latent TB infection aims to prevent progression to active tuberculosis by eradicating dormant bacilli, and the duration of drug therapy with isoniazid influences how well this protection lasts. The traditional and standard regimen with isoniazid is nine months of daily therapy, which provides strong protection against reactivation while maintaining manageable safety and adherence for most patients. There are shorter or alternative regimens, such as rifampin-based or rifapentine-based courses, but those are not isoniazid-only regimens. Ethambutol is not used for latent TB infection. So the duration that best fits the question for isoniazid preventive therapy is nine months.