Geeta Rani Geeta Rani Asked 9 months ago

What does a positive tb shot look like?

My son had a TB shot (Mantoux test) at school and I need to check his arm. What does a positive reaction to a TB shot look like? Should I expect a red, raised bump or something else?

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8 answers

Ritu Mehta Ritu Mehta Joined Jan 2026 9 months ago
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Actually, it's a TB skin test, not a shot, for diagnosis. A positive one looks like a firm, raised, red bump at the site, which gets measured by the nurse or doctor after 48-72 hours. While diet is crucial for overall immunity, especially vegetarian protein sources, this test result needs medical interpretation. Focus on nourishing your body, but let the experts handle the diagnosis.

Ashok Kumar Ashok Kumar Joined Apr 2026 6 months ago

Hello! Just to clarify, it's a TB skin test (Mantoux test), not a 'shot' in the sense of a vaccine. A positive result on this test is characterized by a firm, raised, red area at the injection site, known as 'induration'. This induration is measured by a healthcare professional within 48 to 72 hours. The size determines if it's positive. It indicates exposure, not necessarily active disease, so further tests follow.

Pranav Gupta Pranav Gupta Joined Jan 2026 9 months ago

Yo, so it's a TB *skin test*, not exactly a shot like a vaccine, just fyi. If it's positive, you'll get a firm, raised bump on your arm, not just a red spot. Like, if you press on it, it feels hard. The nurse will measure how big that bump is after a couple of days to tell if it's positive or not. Don't stress too much if it's red, it's the hardness that matters!

Shruti Rao Shruti Rao Joined Mar 2026 8 months ago

So, for a positive TB skin test (it's not really a shot for treatment, more of a diagnostic test), what they look for is a hard, raised bump, not just redness. Like, if you run your finger over it, you'd feel a definite bump. It usually gets red too, but the hardness is key. The doctor or nurse will measure it properly within a few days.

Kunal Sharma Kunal Sharma Joined May 2026 6 months ago

Honestly, after pulling an all-nighter, everything looks blurry, but a positive TB skin test is supposed to be a noticeable, hard, raised bump, not just a red patch. I remember my friend showed me his, it was like a small button under the skin. They measure the bump. My brain can barely measure my sleep deficit, let alone a skin reaction, so best to let the doc do it!

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Divya Sharma Divya Sharma Joined Feb 2026 8 months ago

A positive TB skin test appears as a firm, raised, red area at the injection site, known as induration. It's measured by a medical professional typically 48-72 hours post-injection. Don't try to interpret it yourself; ensure you return for the official reading. This saves time and ensures correct next steps are taken promptly.

Vikram Rathore Vikram Rathore Joined May 2026 5 months ago

A 'positive TB shot' is a misnomer; it's a skin test, not a shot. And relying on what you think it 'looks like' is a huge mistake. Only a trained healthcare professional can accurately measure the induration (the hard, raised area, not just redness) at the correct time to determine a positive result. Do not self-diagnose based on pictures or descriptions online. Go back to the doctor for the reading.

Sunita Devi Sunita Devi Joined Jun 2026 5 months ago

In my time, we just called it the TB test. If it was positive, it meant a raised, hard lump would form where they put the medicine. It wasn't just a red mark, it was a definite swelling that you could feel. This indicates past exposure to TB, and the doctor would then decide if further treatment was needed. Don't worry, they know what to do.

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