Which statement about regimens for TB treatment is true?

Which statement about regimens for TB treatment is true?

• A. The four-drug regimen of INH, rifampin, pyrazinamide, and ethambutol is used initially
• B. Only INH is used for initial TB treatment
• C. INH, Rifampin, and Pyrazinamide are used initially
• D. Pyrazinamide alone is sufficient for active TB

Answer: (C)

TB treatment begins with using multiple drugs at the same time to prevent the bacteria from developing resistance. From the start, isoniazid, rifampin, and pyrazinamide are included in the initial intensive phase because each drug acts on a different target in the bacteria, and using them together greatly reduces the chance of resistance compared with using a single drug alone. Ethambutol is often added as well to cover potential resistance until drug susceptibility is known, but the trio listed is definitely used at the start. The other statements imply monotherapy or omit drugs that are essential to the initial regimen, which is why they aren’t correct.

TB treatment begins with using multiple drugs at the same time to prevent the bacteria from developing resistance. From the start, isoniazid, rifampin, and pyrazinamide are included in the initial intensive phase because each drug acts on a different target in the bacteria, and using them together greatly reduces the chance of resistance compared with using a single drug alone. Ethambutol is often added as well to cover potential resistance until drug susceptibility is known, but the trio listed is definitely used at the start. The other statements imply monotherapy or omit drugs that are essential to the initial regimen, which is why they aren’t correct.