Thyroid Function Testing
Your thyroid governs metabolism, energy, mood, weight, temperature and much more - and thyroid problems are common, especially in women. Whether you're investigating fatigue, unexplained weight changes, hair loss or mood shifts, or you want to monitor a known thyroid condition, our thyroid tests measure the full picture from a simple TSH check to a complete panel with antibodies. Read 8 signs your thyroid may be the problem. Order online, no GP referral needed.
Want to check your thyroid function?
A thyroid function test measures TSH, free T3 and free T4 - the core markers that show whether your thyroid is underactive, overactive or working normally. It's the usual starting point when investigating fatigue, weight changes or mood symptoms.
Measure TSH, free T3 and free T4 — the core markers for understanding your thyroid levels.
Comprehensive thyroid panel including TSH, T3, T4 plus thyroid antibodies for a detailed thyroid profile.
Our most complete thyroid panel: TSH, free T3, free T4, reverse T3 plus three thyroid antibodies for a full picture.
Could it be Hashimoto's or an autoimmune thyroid condition?
Many thyroid problems are autoimmune - Hashimoto's (underactive) and Graves' (overactive) involve the immune system attacking the thyroid. Thyroid antibody testing helps identify whether an autoimmune process is involved, which matters for how a condition is monitored. Discuss results with your GP. For the broader picture, explore our immunity & autoimmunity testing.
Comprehensive thyroid panel including TSH, T3, T4 plus thyroid antibodies for a detailed thyroid profile.
Our most complete thyroid panel: TSH, free T3, free T4, reverse T3 plus three thyroid antibodies for a full picture.
Test TPO and TG antibodies — markers relevant to autoimmune thyroid conditions such as Hashimoto's or Graves'.
Is your thyroid getting the nutrients it needs to work?
Your thyroid can't make or activate its hormones without the right raw materials. Iodine is the backbone of the hormone itself, while selenium, zinc and copper drive how it converts and regulates. Getting these wrong - too little, or with iodine too much - can quietly undermine thyroid function even when standard tests look normal. Testing your cofactors shows whether the supporting nutrients are in the right range, so any correction is targeted rather than guessed. Discuss results with your practitioner, particularly before supplementing iodine.
Test selenium and iodine - essential cofactors your thyroid needs to produce hormones effectively.
An iodine loading test, also known as an iodine challenge test, is used to determine how effectively the body absorbs and uses iodine. The iodine loading test can be useful in assessing iodine deficiency.
Copper and zinc are essential nutrients in our body and they work together. There are many problems that can occur if we have a copper and zinc imbalance.
Is your thyroid affecting your cycles, fertility or weight?
Thyroid hormones strongly influence menstrual cycles, fertility, mood and metabolism. If you're investigating these, our thyroid tests pair well with focused women's health & fertility testing or weight & metabolism testing.
Measure TSH, free T3 and free T4 — the core markers for understanding your thyroid levels.
Comprehensive thyroid panel including TSH, T3, T4 plus thyroid antibodies for a detailed thyroid profile.
Frequently Asked Questions
How i-screen works
Order online
Choose your preferred blood test and place your order securely through our website.
Receive pathology request form
We'll email you your pathology request form, which you'll need for your blood draw.
Visit a Collection Centre
Take your pathology request form to one of our affiliated collection centres for your blood sample.
Get your results
Your results are typically available within 48 hours depending on the test. We'll notify you by email when your results are ready to view in your i-screen dashboard.
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