What is hyperthyroidism?
Your thyroid is a small, butterfly-shaped gland at the base of your neck, just below your Adam’s apple. Hyperthyroidism is a condition where a person’s thyroid is overactive, meaning that it produces excessive amounts of thyroid hormones. The thyroid gland has an enormous impact on your health. Every aspect of your metabolism is regulated by thyroid hormones
What are the symptoms of hyperthyroidism?
When the thyroid gland is overactive the body’s processes speed up and you may experience :
- Neck swelling from an enlarged thyroid gland (goitre)
- Anxiety and irritability or trouble sleeping
- Trembling hands, or tremor
- Heat intolerance
- Palpitations or fast heart rate
- Tiredness and weakness, especially in the arms and thighs
- Unintentional weight loss, even when your appetite and food intake stay the same or increase
- Diarrhoea frequent bowel movements
- In women, hyperthyroidism can affect the menstrual cycle and make it harder to conceive
- Protruding dry eyes and people with Graves’ disease
Sometimes the symptoms are so subtle that they go unnoticed for a long time. In other cases, they come on suddenly over a period of a few days or weeks and severe.
What causes hyperthyroidism?
Graves’ disease is the most common cause of hyperthyroidism. It is an autoimmune condition where the body’s immune system turns against the thyroid gland which in response becomes overactive.
The disease tends to run in families and stress also seems to play a role in the development of symptoms
Hyperfunctioning thyroid nodules (toxic adenoma, toxic multinodular goitre). This form of hyperthyroidism occurs when one or more benign lumps which have developed in your thyroid produce too much thyroid hormone.
Thyroiditis. Sometimes your thyroid gland can become inflamed after pregnancy or a viral infection. The inflammation can cause excess thyroid hormone stored in the gland to leak into your bloodstream. This type of hyperthyroidism is usually temporary and does not need medication
Is there a test for hyperthyroidism?
- Yes, your doctor can arrange a blood test checking your thyroid function.
- If the blood test indicates a problem then further tests may be required such as checking your thyroid antibodies
- Your doctor may organise a thyroid uptake scan
- If you have swelling in the neck then your doctor may organise a thyroid ultrasound
How is hyperthyroidism treated?
Left untreated hyperthyroidism can lead to heart failure, irregular heart rate, osteoporosis (brittle bones) and other complications particularly in older people.
Hyperthyroidism can be treated with
- Antithyroid medicines such as carbimazole or propylthiouracil act by reducing the amount of hormones your thyroid gland makes. Typically they take a few weeks to bring your thyroid hormones under control.
- Beta-blockers such as propranolol help alleviate the symptoms and make you feel more comfortable until your thyroid imbalance is in control
- Radioactive iodine
- Radioactive iodine is given orally, either as a pill or in liquid form, and destroys the cells that produce thyroid hormones. However scary this may sound, the treatment is safe. However, it cannot be given to women who are pregnant and pregnancy should be avoided for at least 6 months after treatment as it can damage the baby’s thyroid gland. Since it uses only a small amount of radiation, it does not increase the chance of getting cancer. Neither does it cause problems getting pregnant or heighten the risk of birth defects in future pregnancies.
- The thyroid or a part of it can be surgically removed. Doctors usually recommend this option in case of a large goitre or in the presence of a thyroid lump where there is a concern that it may be malignant.
Most people who are treated with radioactive iodine or who have surgery end up producing insufficient amounts of thyroid hormones after treatment and usually need to take thyroid hormone replacement for the rest of their lives.
What if I want to conceive?
- If you take anti-thyroid medicine, talk to your doctor before you start trying to get pregnant. You will probably need to take different medicines at different times during your pregnancy and your doses may need to be adjusted.
- If you were treated with radioactive iodine, it is advisable to wait at least six months before you start trying for a baby. This will give your doctor enough time to find out if your thyroid is producing sufficient amounts of hormones after the treatment. If your thyroid hormone levels turn out to be too low, you will need to take thyroid hormone pills. It is important for your body to have healthy levels of thyroid hormones before you get pregnant to avoid risks to you and your baby.
- Whatever treatment you use, make sure you have your thyroid hormone levels checked regularly during pregnancy.
By Dr Mohgah Elshiekh