LTBI Treatment: What You Need to Know

If a test shows you have latent tuberculosis infection (LTBI), you don’t feel sick, but the bacteria are hanging out in your lungs. The goal of treatment is simple – kill those germs before they turn into active TB. That means taking medicine for a set period, usually months, and staying on track.

The good news is that there are a few proven regimens, and doctors pick one based on your health, how likely you are to stick with it, and any other meds you’re taking. Most of the time the choice comes down to a single drug taken daily or a short course of two drugs taken together.

Main Drug Regimens

Isoniazid (INH) 9‑month course is the classic option. You take a daily tablet, and the dose is calculated by your weight – roughly 5 mg per kilogram, up to a maximum of 300 mg. It’s cheap and well‑studied, but you need to stay on it for nine months, which can be a hassle.

Rifampin (RIF) 4‑month course offers a shorter timeline. The typical dose is 10 mg per kilogram, max 600 mg per day. Many people prefer it because you finish sooner, but it can interact with a lot of other drugs, so tell your doctor about any prescriptions you already have.

INH + Rifapentine (3HP) weekly is a newer, once‑weekly regimen for three months. The dose is weight‑based – about 15 mg/kg of isoniazid and 900 mg of rifapentine per dose. This plan cuts down on pill fatigue, but you need a clinic that can give you the drugs under direct observation.

All three options work well when taken correctly. The biggest difference is how long you stay on therapy and how many side‑effects you might notice.

Tips for Staying Safe

Side‑effects are the main reason people stop early. With isoniazid, watch for mild liver stress – you might feel a bit of nausea or notice yellowing of the skin. Rifampin can turn urine and tears orange, which is harmless but surprising. If you feel persistent fatigue, rash, or any weird symptoms, call your health‑care provider right away.

Because dosing depends on weight, keep your scale handy. If you lose or gain a lot of weight during treatment, ask your doctor to re‑check the dose.

Take the medication at the same time each day. Pair it with food if stomach upset is an issue, but try to avoid dairy or antacids close to the dose because they can lower absorption.

Never stop the pills without talking to a professional, even if you feel fine. Stopping early can let the bacteria survive and increase the chance of active TB later.

Finally, keep a simple log – write down the date and whether you took the dose. A quick note on your phone or a paper calendar works wonders for staying on track.

With the right regimen and a few easy habits, treating LTBI is straightforward and keeps you from developing active tuberculosis down the road.