Graves disease is an autoimmune condition in which your immune system attacks your thyroid gland, causing it to produce far more hormones than your body needs. It’s the most common cause of hyperthyroidism, responsible for 60% to 80% of all cases. The condition affects women disproportionately, with a lifetime risk of about 3% in women compared to 0.5% in men, and it most often appears between the ages of 20 and 50.
What Happens Inside Your Body
Your thyroid is a butterfly-shaped gland at the base of your neck that controls your metabolism. Normally, your brain sends a chemical signal called TSH to tell the thyroid how much hormone to make. In Graves disease, your immune system produces antibodies that mimic that signal. These antibodies latch onto the same receptors on thyroid cells that TSH uses, but with a critical difference: once attached, they lock the receptor into its “on” position. The receptor can’t switch back off while the antibody is bound to it, so the thyroid keeps churning out hormones long after your body has more than enough.
This prolonged activation is what makes Graves disease distinct from other causes of an overactive thyroid. Your body isn’t just temporarily overproducing hormones. It’s being continuously told to produce more by a misdirected immune system.
Common Symptoms
Because thyroid hormones affect nearly every system in your body, Graves disease casts a wide net of symptoms. Most people notice some combination of the following:
- Unexplained weight loss even with a normal or increased appetite
- Rapid or irregular heartbeat, sometimes with palpitations
- Anxiety, irritability, and trouble sleeping
- Trembling hands and muscle weakness
- Heat intolerance and excessive sweating
- More frequent bowel movements
- An enlarged thyroid (goiter) visible or palpable at the front of the neck
Fatigue is a paradox of Graves disease. Even though your metabolism is running hot, many people feel profoundly tired because the body is essentially burning through its energy reserves at an unsustainable rate.
Eye Problems in Graves Disease
Graves disease can cause a separate but related condition called thyroid eye disease, where the immune system also attacks the tissues around the eyes. The most common sign is upper eyelid retraction, where the eyelids pull back to show more white above the iris. This occurs in over 90% of people with thyroid eye disease. About 60% develop noticeable bulging of the eyes, and half have difficulty fully closing their eyelids.
Eye muscle dysfunction affects roughly 40% of patients and can cause double vision. About 30% experience a dull, pressure-like pain behind the eyes. In severe cases, around 6% of people develop some degree of vision loss or color vision changes from the swollen tissues pressing on the optic nerve. Not everyone with Graves disease develops eye problems, but those who do may notice eye symptoms appearing before, during, or even after the thyroid condition is treated.
Skin Changes
A small number of people with Graves disease develop a skin condition called pretibial myxedema. The skin on the shins (and occasionally the tops of the feet) becomes reddish, thick, and rough in texture. It’s uncommon, but it’s a distinctive hallmark of Graves disease rather than other thyroid disorders.
Who Is at Risk
Women are about six times more likely than men to develop Graves disease. Beyond sex, several environmental factors raise your risk. Smoking is a well-established trigger, and the risk increases with the number of cigarettes smoked. Stressful life events have also been linked to the onset of the disease, as have periods of high dietary iodine intake. Having other autoimmune conditions, such as type 1 diabetes or rheumatoid arthritis, increases your likelihood as well, since autoimmune diseases tend to cluster together.
How Graves Disease Is Diagnosed
Diagnosis typically starts with a blood test measuring TSH, the hormone your brain sends to regulate your thyroid. In Graves disease, TSH drops to very low levels, usually below 0.05 mU/L, because your brain senses the flood of thyroid hormones and stops sending the signal. As the disease progresses, blood levels of the active thyroid hormones (called free T3 and free T4) rise above normal.
To confirm that the hyperthyroidism is specifically caused by Graves disease and not another condition, doctors test for thyroid receptor antibodies (TRAb). These are the misguided immune proteins driving the disease. This antibody test is about 95% accurate, approaching nearly 100% with newer testing methods. In some cases, an imaging scan that shows how your thyroid absorbs iodine can provide additional confirmation.
Treatment Options
There are three main approaches to treating Graves disease, and the right choice depends on your age, the severity of your symptoms, whether you’re pregnant or planning to be, and your personal preferences.
Antithyroid Medication
Medication is often the first-line treatment, particularly outside the United States. It works by blocking the thyroid’s ability to produce hormones. The starting dose is adjusted based on how overactive your thyroid is, then gradually reduced over several weeks as hormone levels stabilize. Most people stay on a maintenance dose for 12 to 18 months. The goal is to quiet the thyroid long enough for the immune system to settle down on its own. In the U.S., about 20% to 30% of patients achieve lasting remission after completing a course of medication, meaning their disease doesn’t come back after stopping treatment. Those who relapse typically move on to one of the more permanent options.
While on medication, you’ll have regular blood tests to monitor thyroid hormone levels. You should also watch for signs of a rare but serious side effect: fever, sore throat, or unusual fatigue, which can signal a drop in white blood cells.
Radioactive Iodine Therapy
Radioactive iodine therapy is the most common treatment for Graves disease in the United States. You swallow a capsule or liquid containing a radioactive form of iodine. Your thyroid absorbs it the same way it absorbs regular iodine from food, but the radiation gradually destroys thyroid cells from within. The treatment specifically targets thyroid tissue, leaving other parts of your body largely unaffected. One dose cures the hyperthyroidism in about 88% of cases.
The tradeoff is that radioactive iodine typically destroys enough of the thyroid that it can no longer produce sufficient hormones on its own. Most people who undergo this treatment need to take a daily thyroid hormone replacement pill for the rest of their lives. For a few days after treatment, you’ll need to take precautions to limit radiation exposure to people around you, especially young children and pregnant women. This treatment is not recommended for people with moderate to severe thyroid eye disease, as it can worsen eye symptoms.
Surgery
Thyroidectomy, or surgical removal of the thyroid gland, is recommended in specific situations: when you have a very large goiter that causes difficulty breathing or swallowing, when a suspicious thyroid nodule needs to be evaluated, when eye disease is too severe for radioactive iodine, or when you’re pregnant or breastfeeding and medication isn’t controlling the disease. It’s also an option if you’ve already tried medication and radioactive iodine without success.
Surgery provides the fastest resolution of hyperthyroidism but carries its own risks. About 12.6% of patients experience temporary low calcium levels afterward (from disruption to the tiny parathyroid glands that sit near the thyroid), though only about 0.5% have permanent issues. There’s also a small risk of vocal cord nerve damage. Like radioactive iodine, surgery means you’ll need lifelong thyroid hormone replacement.
Thyroid Storm: A Rare Emergency
Thyroid storm is the most dangerous complication of untreated or poorly controlled Graves disease. It’s a sudden, life-threatening surge in thyroid hormone activity that can be triggered by infection, surgery, or stopping medication abruptly. Symptoms include high fever (above 100.4°F), rapid heart rate, agitation or confusion that can progress to delirium or seizures, vomiting, diarrhea, and even heart failure. Thyroid storm requires emergency treatment. It’s rare, but it’s one of the reasons Graves disease needs to be managed even when symptoms feel tolerable.
Living With Graves Disease Long-Term
Regardless of which treatment path you follow, Graves disease requires ongoing monitoring. If you achieve remission with medication, you’ll still need periodic blood tests to catch a relapse early. If your thyroid has been destroyed or removed, your daily hormone replacement pill effectively becomes your thyroid, and finding the right dose takes some fine-tuning over months. Most people on stable replacement therapy feel completely normal and have no restrictions on their daily lives.
The autoimmune component of Graves disease doesn’t always disappear even when the thyroid problem is resolved. Eye symptoms, for instance, can develop or worsen independently of thyroid hormone levels. Staying aware of changes in your vision, eye comfort, or the appearance of your eyes remains important even years after treatment.