Hypothyroidism, also known as an underactive thyroid, occurs when the thyroid gland in your neck does not produce enough thyroid hormone. These hormones help regulate your metabolism, energy levels, and many important body functions.
Common symptoms
Symptoms of hypothyroidism often develop gradually and can include tiredness and low energy, feeling cold more easily than usual, weight gain, constipation, dry skin, hair thinning or coarse hair, low mood, irregular menstrual periods, and difficulty getting pregnant.
Possible causes
Common causes include autoimmune thyroid disease (Hashimoto's thyroiditis), thyroid surgery, radioiodine treatment, radiation to the neck area, and certain medications. Less commonly, problems with the pituitary gland can also reduce thyroid hormone production.
How is it diagnosed?
A simple blood test measuring TSH (thyroid stimulating hormone) and thyroxine levels can usually confirm the diagnosis. Your doctor may also check thyroid antibodies and review your symptoms and medical history.
Treatment
Treatment usually involves taking Levothyroxine once daily. This replaces the hormone your thyroid is unable to produce. Most people require lifelong treatment, with occasional blood tests to ensure the dose remains correct.
Pregnancy and thyroid health
If you are pregnant or planning a pregnancy, thyroid hormone levels should be monitored closely, as your medication dose may need adjustment. Untreated hypothyroidism in pregnancy can affect both mother and baby.
When to see your doctor
If you have ongoing tiredness, unexplained weight gain, constipation, dry skin, hair thinning or other symptoms listed above, it may be worth having your thyroid function checked.
Key takeaways
- Hypothyroidism means the thyroid gland is underactive and produces too little hormone.
- A simple blood test measuring TSH and thyroxine confirms the diagnosis.
- Daily Levothyroxine is the standard treatment and is usually lifelong.
- Thyroid levels need close monitoring during pregnancy.