Chronic Conditions
    Updated at: October 17, 20244 min read

    How to find out if you have an underactive thyroid

    It’s easy to know when you have a cold or a chest infection because symptoms are usually unpleasant and quick to make themselves known. Considering we rely so heavily on symptoms to tell us when we’re unwell, conditions that have ones that are silent, slow to develop or not present at all can be a little tricky.

    Key Takeaways

    Underactive thyroid symptoms can be slow and tricky to spot:

    Hypothyroidism symptoms like tiredness, weight gain, and depression develop gradually and can be confused with other conditions. You may also experience muscle aches, constipation, sensitivity to cold, and changes in libido or menstrual cycles.

    A simple blood test can diagnose hypothyroidism:

    Blood tests can reveal low levels of thyroid hormones (T3 and T4) and high levels of thyroid-stimulating hormone (TSH), indicating the thyroid isn't working properly. Early detection can help manage future risks.

    Untreated hypothyroidism can lead to serious health risks:

    While the symptoms may seem mild, untreated hypothyroidism can raise cholesterol levels and increase the risk of heart problems like angina or heart attacks. Treatment involves daily thyroid hormone medication like Levothyroxine to restore normal levels.

    The symptoms to look out for:

    Symptoms of an underactive thyroid (or hypothyroidism) can be difficult because they can be extremely slow to appear and they’re often similar to symptoms of other conditions. However, the main things you should look out for are tiredness, weight gain and depression.

    Along with the main symptoms, others include constipation, muscle aches and being sensitive to the cold. An underactive thyroid can also mess with your libido and menstrual cycle (women), so the condition can make you less interested in sex or can cause irregular or heavy periods.

    How do you diagnose an underactive thyroid?

    Although pinpointing the suspected cause of the symptoms can be hard, diagnosis of the condition is actually pretty simple.

    Your blood is a fascinating collection of information and can tell you all sorts of things, from your testosterone levels to your blood cell count. It can also tell you your levels of thyroid-producing hormones such as triiodothyronine (T3) and thyroxine (T4).

    A doctor pointing to a model of a thyroid gland

    In a blood test, people suffering with an underactive thyroid will show low levels of these hormones, which is evidence that the thyroid gland is not working as it should. If your blood results show normal levels of thyroxine but high levels of thyroid-stimulating hormone (TSH) then it could mean you’re at risk of developing an underactive thyroid in the future.

    Why is it important to diagnose and treat an underactive thyroid?

    Although the symptoms may not show straight away and may not cause you excessive pain or discomfort, an underactive thyroid puts you at risk of more serious conditions in the future. 

    Your thyroid gland is responsible for the way your body processes fat, hence why a symptom of an underactive thyroid is weight gain. But this can also cause high cholesterol and clogging of the arteries, which can increase your risk of angina and heart attack.

    Although an underactive thyroid may not present any immediate risks, it’s important to treat it effectively and get your thyroid hormones back to a normal level to avoid potential health problems in the future.

    Treatment involves taking a daily medication to replenish your low thyroid hormone levels. It may take some trial and error to work out your correct dosage (since everyone is different) but once you’ve got it right, you should see the health rewards in the long term.

    You can find effective hypothyroidism treatments at UK Meds including Levothyroxine and Liothyronine. Levothyroxine is by far the most popular treatment option but Liothyronine is a valuable alternative for people whose bodies can’t process the T4 hormone. However, you should always return to your GP for regular blood tests and monitoring to ensure you're on the correct dosage.

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