Which TB regimen duration corresponds to 9 months?

Which TB regimen duration corresponds to 9 months?

• A. Rifampin for 4 months
• B. Isoniazid for 9 months
• C. Rifampin + Isoniazid for 3 months
• D. Isoniazid for 6 months

Answer: (B)

Treating latent TB infection centers on preventing reactivation by eradicating dormant bacteria. The standard approach with isoniazid alone is nine months, which provides strong protection against progression to active TB and is commonly recommended when there are no contraindications. Among common regimens, shorter options exist—four months of rifampin, or six months of isoniazid, or a short three-month course with rifampin and isoniazid—but these do not amount to nine months of isoniazid. Therefore, the duration that corresponds to nine months is isoniazid for nine months.

Treating latent TB infection centers on preventing reactivation by eradicating dormant bacteria. The standard approach with isoniazid alone is nine months, which provides strong protection against progression to active TB and is commonly recommended when there are no contraindications. Among common regimens, shorter options exist—four months of rifampin, or six months of isoniazid, or a short three-month course with rifampin and isoniazid—but these do not amount to nine months of isoniazid. Therefore, the duration that corresponds to nine months is isoniazid for nine months.