Overactive Thyroid
See your GP if you think you may have an overactive thyroid (hyperthyroidism).
A diagnosiswill be based on your symptoms and the results of a blood testthat assesses how well your thyroid is working.
Your GP maytake a sample of bloodand send it to a laboratory to check your hormone levels. This is known as a thyroid function test.
It's used to checkthe levels of:
Yourlevels will be compared towhat's normal for a healthy person. A low level of TSH and high levels of T3 and/or T4 usually means you have an overactive thyroid.
What are considered normal levelsvariesdepending on things such as your age and the exact testing technique used by the laboratory.
Ifyou have high thyroid hormone levels, you may be referred to a specialist for the tests belowto find out what's causing it.
Another blood test may be carried out tolook for anti-thyroid antibodies.
These are usually found ifyou have Graves' disease , a common cause of an overactive thyroid.
A blood test called erythrocyte sedimentation rate (ESR) may also be done to check for inflammation in your body.
If there are signs of inflammation, it may mean the increase in thyroid hormones is caused by Thyroiditis (inflammation of the thyroid).
A thyroid scan maybedone to look for problems such as lumps (nodules) onyour thyroid.
For the test, you'll be asked to swallow or have an injection of a small amount of a slightly radioactive substance that will be absorbed by your thyroid.
A scan is then carried out to see how much of the substance has been absorbed and toexamine the size and shape of your thyroid.
Find out about an overactive thyroid (hyperthyroidism), including what the symptoms are, why it happens and how it's treated.
Find out about the main symptoms of an overactive thyroid (hyperthyroidism) and when to get medical advice.
Find out about the main causes of an overactive thyroid (hyperthyroidism), such as a condition called Graves' disease.
Find out about the main tests used to diagnose an overactive thyroid (hyperthyroidism), including a thyroid function blood test.
Find out about the main treatments for an overactive thyroid (hyperthyroidism), including medication and surgery.
Find out about the complications that can occur as a result of an overactive thyroid (hyperthyroidism), including eye problems and pregnancy problems.