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Thyroid Check

A popular thyroid blood test which examines levels of TSH and free thyroxine (FT4) to help in the diagnosis of a thyroid disorder.

Most investigations into a thyroid disorder begin by testing levels of thyroid stimulating hormone (TSH) and free thyroxine (FT4). TSH is produced by the pituitary gland to stimulate the thyroid to produce more thyroid hormones. Thyroxine (T4) is the main thyroid hormone produced by the thyroid gland - this test measures the amount of free T4 (T4 which is not bound to protein) in the blood. An elevated TSH and low FT4 reading suggests an underactive thyroid (hypothyroidism) whereas low TSH and raised FT4 indicates an overactive thyroid (hyperthyroidism).

Who is this blood test for

The Thyroid Check blood test is for individuals who wish to assess their thyroid function.

Thyroid problems affect up to 3% of the adult population. Although symptoms are non-specific and often begin mildly they may become debilitating if left untreated. Both an underactive and an overactive thyroid can cause a swelling of the gland (goitre) but many symptoms can be present without this classic sign.

Symptoms of hypothyroidism include lethargy and excessive sleeping, difficulty in losing weight or constant weight gain despite not eating more, feeling cold when others are warm, constipation, dry hair and brittle nails, depression, slow heartbeat, muscle aches and pains and fertility problems.

Symptoms of hyperthyroidism include feeling fidgety and nervous, trouble sleeping, tremors, unexplained weight loss, frequent bowel movements or diarrhoea, feeling hot and sweaty, hair loss, palpitations, muscle weakness and fertility problems.

What's included

Thyroid Stimulating Hormone is produced in the pituitary gland and stimulates the thyroid gland to produce thyroid hormones thyroxine (T4) and triiodothyronine (T3).

High levels of TSH indicate an underactive thyroid while low levels indicate an overactive thyroid. In primary pituitary failure, a low TSH will be associated with an underactive thyroid.

Thyroxine (T4) is one of two hormones produced by the thyroid gland. Most T4 is bound to carrier proteins in the blood - this test measures the level of T4 which is free, or unbound, circulating in your blood.

High levels of free thyroxine can indicate an overactive thyroid while low levels can indicate an underactive thyroid.

We will send you your Thyroid Check finger-prick blood and sample collection kit which contains everything you need to take your blood and sample in the comfort of your own home. If you are unsure about completing a finger-prick blood sample collection you will have the opportunity to select a clinic-based venous blood sample collection or choose to go our London laboratory during the checkout process.

Your Thyroid Check includes 1st class postage and packaging for you to send your blood and sample directly to our laboratory for analysis. If you live in an area where you cannot rely on the post or you simply want to ensure that your sample arrives at the laboratory the following day, you may wish to send your blood and sample guaranteed next day delivery for extra reassurance.

Your blood and sample will be analysed at one of our chosen laboratories. You can be assured of fast, accurate results from one of our accredited independent providers of clinical diagnostic tests.
Once you have placed your order you will receive login details to where you can manage your account, track your orders and view your Thyroid Check results in your own personal dashboard.
Our medical team will comment on out-of-range blood and results and give you follow-up advice where necessary. If you need it, a PDF copy of your Thyroid Check results can be downloaded for your doctor. Want a hard-copy report? You will be given the opportunity to order one during the checkout process.

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Thyroid Check is included in the following categories: Thyroid HealthFatigue