How long is the typical duration for INH treatment in latent TB infection?

The typical duration for isoniazid (INH) treatment in latent tuberculosis (TB) infection is 6 to 9 months. This duration is recommended to effectively reduce the risk of developing active TB disease. INH works by targeting the bacteria responsible for TB, and a treatment period of 6 to 9 months ensures that the latent infection is adequately treated, minimizing the possibility of progression to active TB.

Health organizations, including the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO), endorse this duration based on extensive research showing that completing the full course significantly lowers the chances of reactivation of TB. Shorter treatment durations, such as 1 to 3 months or 3 to 6 months, may not provide sufficient coverage for individuals at risk, while extending treatment to 12 months could lead to higher rates of non-compliance and potential side effects without additional benefits. Thus, the 6 to 9 month timeline strikes a balance between efficacy and practicality.