Hyperthyroidism involves the thyroid gland producing many thyroid hormones. This overproduction can have different effects on women and men.
A woman with hyperthyroidism may experience symptoms that involve menstruation and pregnancy, while men may experience sexual dysfunction, for example. Hyperthyroidism can also cause a wide range of universal symptoms.
In this article, we describe the general and sex-specific symptoms of an overactive thyroid. We also explain how doctors diagnose the problem and what its treatment involves.
Hyperthyroidism is when the thyroid, a butterfly-shaped gland located in the neck, produces an excess of hormones called thyroxine (T4) and triiodothyronine (T3).
The high levels of these hormones can have a wide range of effects on the body. A person can, for example, experience:
When hyperthyroidism results from an underlying autoimmune disease called Graves’ disease, a person may also have:
- inflammation of the eyes
- bug-eyed
- a skin disease called pre-tibial myxedema, which tends to give the lower legs a swollen and bulging appearance
Hyperthyroidism is two to ten times more likely to affect women than men, and the risk increases after menopause and directly after pregnancy.
Thyroid hormones help regulate the menstrual cycle, and overproduction can cause:
- interruptions, including irregular or lighter periods
- difficulties to get pregnant
- health problems during pregnancy for the person and the fetus
Pregnancy increases the level of thyroid hormones in the blood, and having hyperthyroidism during pregnancy can lead to:
- pre-eclampsia, a potentially serious condition that causes hypertension and kidney problems
- thyroid storm, a severe worsening of the symptoms of hyperthyroidism
- premature birth
- a birth weight below 5 pounds
- problems with your baby’s heart, including a faster heart rate, which can lead to serious complications
- loss of pregnancy
In addition, some researchers have found that hyperthyroidism leads to reduced libido in women.
For men, having an overactive thyroid can cause:
A 2019 review found that symptoms related to sexual dysfunction were present in 48–77% of men with the disease. Although the evidence is contradictory, hyperthyroidism can also lead to low libido in men.
If a doctor suspects hyperthyroidism, he or she will check the person’s medical history and have a test to check for signs of an enlarged thyroid in your neck.
The symptoms of hyperthyroidism are wide-ranging and overlap with those of many other conditions. Its increased prevalence after pregnancy and menopause, both times of significant hormonal changes, can make symptoms more difficult to distinguish.
Because of this, instead of relying solely on symptoms, doctors usually order a blood test to check for thyroid function. The results reveal the level of thyroid hormones in the blood.
In some cases, additional testing is required. For example, a doctor may order an iodine absorption test to determine if Graves’ disease is responsible for a person’s hyperthyroidism.
The goal of treatment is to bring thyroid hormone levels to the normal range and thereby reduce the symptoms of hyperthyroidism.
The specific approach depends on several factors, including the person’s age, the presence of other health conditions and the severity of the symptoms.
Antithyroid drugs, such as methimazole (Tapazole), reduce the production of thyroid hormones. Doctors generally need to adjust the dosage of these medications over time. They usually perform blood tests every 2-3 months to ensure the correct dosage, reducing the frequency of these tests every 6-12 months for long-term treatment.
Doctors can also prescribe other medications. Beta-blockers, for example, can help treat symptoms such as nervousness and shaky hands.
Antithyroid drugs can cause side effects, including low white blood cell count or liver problems.
Another treatment option is radioiodotherapy, which involves taking a capsule or liquid containing radioactive iodine-131. This substance destroys the cells of the thyroid gland without affecting other tissues.
Radioiodine therapy often leads to hypothyroidism, in which levels of thyroid hormones are very low. However, this condition is easier to treat than hyperthyroidism.
In cases where other treatments do not work, the doctor may recommend surgery to remove part or all of the thyroid gland. This procedure is called thyroidectomy.
Hyperthyroidism can be difficult to detect because its symptoms are very broad and overlap with many other health problems.
Anyone who suspects they have a thyroid problem should see a doctor immediately. Some warning signs include:
- unexpected changes in weight
- changes in appearance, such as thinning hair and skin
- persistent tiredness and mood swings
- constantly feeling very hot or cold
- missing a period without being pregnant
Hyperthyroidism occurs when the thyroid, a gland in the neck, produces excess thyroid hormones. It can cause a wide range of symptoms, some of which are sex specific.
The condition is more common in women than in men and can cause problems with menstruation and pregnancy. In men, the disease can affect sexual functioning and cause enlarged breast tissue.
Doctors use a blood test to diagnose hyperthyroidism. Various medications and therapies are available, which can reduce symptoms and regulate hormone levels.