Hyperthyroidism: Signs, symptoms, causes and more

Your thyroid is a small but mighty hormone gland in your neck that plays a big role in your health. Hyperthyroidism, a type of thyroid disease also called overactive thyroid, occurs when your thyroid gland makes more hormones than your body needs. An increase in the hormone thyroxine (T4) increases metabolism, which means the pace of many of your body’s functions speeds up.

“People with hyperthyroidism often like it because, with the increased metabolism, they’re losing weight,” said Deepika Reddy, MD, an endocrinologist on the medical staff at Baylor University Medical Center. “It’s as if your body is revved up in overdrive.”

More energy and weight loss may seem like a good thing initially—but too much thyroid hormone in the body could lead to other health problems. Here’s what you need to know if you’re worried about thyroid problems.

Symptoms of hyperthyroidism

Because the thyroid hormone regulates metabolism, overproduction can cause a wide variety of symptoms, including

• Unintentional weight loss
• Hand tremors
• Rapid or irregular heartbeat
• Heat sensitivity
• Diarrhea
• Anxiousness
• Protruding eyeballs
• Limited range of motion in the eyes
• Warm or clammy skin
• An enlarged thyroid gland (goiter)

Causes of hyperthyroidism

There are a variety of reasons your thyroid may make too much thyroid hormone, including:

• Graves’ disease – an autoimmune disorder
• An enlarged thyroid gland (toxic nodular goiter)
• Inflammation of the thyroid gland that can present as thyroiditis, Hashimoto’s disease, postpartum thyroiditis or subacute thyroiditis

Diagnosing and treating hyperthyroidism

Because so many symptoms of hyperthyroidism are similar to other conditions, your doctor may run a series of thyroid function blood and imaging tests to confirm a diagnosis. This may include blood tests to measure your TSH, T3, T4 and thyroid antibody levels. Ultrasounds are also used if your doctor suspects thyroid nodules.

Your treatment depends on a variety of factors.

“If you are very thyroid toxic, we start with medications to suppress the production of thyroid hormone to cool the gland down and make you less symptomatic,” Dr. Reddy said.

Other treatment options include radioactive iodine ablation and thyroid surgery. Let’s talk about what to expect with each of these options.

Radioactive iodine ablation

Treating an overproducing thyroid gland with radioactive iodine ablation is a good option for many patients, as there are minimal side effects.

With this treatment, you’ll receive iodine-131, which is picked by your cells and then destroys the cells that are overproducing, Dr. Reddy said.

In some cases, however, you may need more than one treatment to achieve stabilized thyroid hormone levels.

“It takes time to see the full effect of the radioactive iodine,” Dr. Reddy said. “You have to struggle with some highs and some lows while the treatment is taking effect and while we’re assessing the outcomes of whether we need to repeat a dose or whether we need to supplement with medication. But, on the other hand, it’s not a surgical intervention.”

Surgery

In most cases, if you have Graves’ disease, your doctor will recommend surgery to remove your entire thyroid gland, Dr. Reddy said.

If there is a single toxic nodule, they may recommend the removal of one lobe of your thyroid.

“Surgery is the more definitive option, but you won’t have a thyroid, and you’ll have to take a replacement for the rest of your life,” Dr. Reddy said.

A thyroidectomy is a generally safe procedure, but complications of thyroid surgery include:

• Bleeding
• Infection
• Low parathyroid hormone levels (hypoparathyroidism) caused by surgical damage or removal of the parathyroid glands.
• Airway obstruction caused by bleeding.
• Permanent hoarse or weak voice due to nerve damage

Surgery is a good choice for people with Graves’ eye disease, Dr. Reddy says, as radioactive iodine ablation can worsen Graves’ ophthalmopathy.

Dangers of untreated hyperthyroidism

If your thyroid gland makes way too much thyroid hormone for a long time —and you’re unaware that you have a problem with your thyroid—you can face long-term effects. If your elevated thyroid levels go untreated, you may develop:

• Tachycardia – increased heart rate
• Dilated cardiomyopathy
• Weakened bones and osteoporosis
• Thyroid storm – a rare but life-threatening condition

“Even subtle hyperthyroidism can have long-term consequences if you don’t treat it,” Dr. Reddy said.

One caution with hyperthyroidism, Dr. Reddy said, is that birth control medications will also be metabolized faster, thereby potentially rendering them ineffective. If you are using hormone therapy for birth control, please notify your doctor if you have elevated levels of thyroid hormone.

Learn more about treatment for thyroid disorders and other endocrine conditions here.