PPD Treatment: What You Need to Know About Testing and Managing Latent TB

When you hear PPD treatment, a process that follows a positive tuberculin skin test to prevent active tuberculosis. Also known as latent TB treatment, it’s not a cure for an active infection—it’s a shield against one. The PPD skin test, or tuberculin skin test, is the first step. It’s simple: a tiny amount of purified protein derivative is injected under the skin on your forearm. After 48 to 72 hours, a healthcare worker checks for swelling. If it’s raised and firm, you’ve likely been exposed to TB bacteria. But here’s the key point—having a positive PPD doesn’t mean you’re sick. It means your body has fought off the bacteria and locked it away. That’s latent TB.

That’s where latent TB, a dormant form of tuberculosis infection with no symptoms and no contagiousness comes in. Left untreated, about 5 to 10% of people with latent TB will develop active disease later in life—especially if their immune system weakens from aging, HIV, diabetes, or steroids. That’s why tuberculin skin test, the standard screening tool used to detect TB exposure results matter. If your test is positive, your doctor will likely order a chest X-ray to rule out active TB. If that’s clear, you’ll start treatment. The most common option is a daily dose of isoniazid for 9 months. There’s also a shorter 3-month combo of isoniazid and rifapentine, taken once a week under direct observation. Both are proven to cut your risk of active TB by over 90%.

Not everyone with a positive PPD needs treatment. Healthy adults with no risk factors might skip it. But if you’re a healthcare worker, recently arrived from a high-TB country, living with someone who has active TB, or have a weakened immune system—treatment is strongly recommended. Side effects like liver stress or nerve tingling happen, but they’re rare and manageable with monitoring. The real danger isn’t the medicine—it’s ignoring the test result. Active TB spreads easily, takes months to treat, and can be deadly. PPD treatment stops it before it starts.

What you’ll find below are real, practical guides on how PPD fits into broader health decisions. From how it compares to blood tests like QuantiFERON, to what to do if you’re allergic to isoniazid, to how pregnancy changes your options—these posts cut through the noise. You won’t find fluff. Just clear, no-nonsense advice from people who’ve been through it.