What Is a Thyroid Scan?
A thyroid scan is a safe imaging test that shows how your thyroid gland is working. It uses a tiny amount of radioactive material (called a tracer) to take pictures of the thyroid.
This scan helps your doctor check for:
- Overactive or underactive thyroid
- Lumps or nodules
- Goitre (enlarged thyroid)
- Signs of thyroid cancer
When Do Doctors Suggest This Test?
Your doctor may ask for a thyroid scan if:
- Your thyroid blood test is abnormal
- There’s a lump in your neck
- You have swelling or pain near the thyroid
- You’ve had thyroid cancer before
How to Prepare for the Test
- No fasting is needed unless your doctor tells you.
- Avoid iodine-rich foods and medicines (like seafood, iodised salt, cough syrups) for 1–2 weeks.
- Stop thyroid medications only if your doctor advises.
- Tell us if you’re pregnant or breastfeeding.
- Remove jewellery and wear clothes that allow access to your neck.
What to Bring With You
- Doctor’s referral or scan form
- Recent blood reports (TSH, T3, T4)
- Past thyroid scan or ultrasound reports
- List of current medicines and supplements
- One family member or friend (optional)
What Happens During the Scan
- Tracer is given – either by injection or as a small capsule.
- Waiting time – usually 20 to 30 minutes to let the tracer absorb.
- The scan – you will lie on a table while the scanner takes images of your neck. This part is painless and takes about 15–30 minutes.
- Stay still during the scan for clear pictures.
How Long Will It Take?
- Tracer administration: 5–10 minutes
- Waiting time: 20–30 minutes (may vary)
- Scanning: 15–30 minutes
- Total time at the centre: Around 1 to 1.5 hours
After the Scan
- You can eat and drink normally.
- Start your medicines again if your doctor allows.
- Drink extra water to help flush out the tracer.
- Avoid close contact with children and pregnant women for 24 hours as a safety step.
- Your report will be sent to your doctor.
Is It Safe?
Yes, thyroid scans are safe. The radiation used is very low and passes out of your body in a few hours. There are no major side effects in most cases.
Simple, safe, and helpful – the thyroid scan gives clear answers about your thyroid health.