Hyperthyroidism and Graves Disease: Symptoms, Testing, and Treatment Options

A racing heart, a body that feels wired, weight loss you did not plan, and nights when you cannot sleep. These can be signs of an overactive thyroid, also called hyperthyroidism. It is much less common than an underactive thyroid, but it is very treatable once it is named. Here is how it is found, what causes it, and what your treatment options look like.

What hyperthyroidism actually is

Your thyroid is a small gland in your neck that sets the pace for how your body uses energy. In hyperthyroidism, it makes too much thyroid hormone, and nearly everything speeds up.

Common symptoms include a fast or irregular heartbeat, tremor, heat intolerance, sweating, anxiety, trouble sleeping, frequent bowel movements, and weight loss despite a normal appetite. Some people mostly feel jittery. Older adults can have fewer classic symptoms and may only notice fatigue, a fast heart rhythm, or weight loss.

The most common cause is Graves disease, an autoimmune condition in which antibodies tell the thyroid to overproduce hormone (Smith and Hegedus, NEJM 2016). Other causes include thyroid nodules that make hormone on their own, and thyroiditis, an inflammation that leaks stored hormone for a short time. The cause matters because it changes the treatment.

How it is diagnosed

Diagnosis starts with blood tests. In typical hyperthyroidism, TSH (the signal from your brain telling the thyroid what to do) is low, while free T4 and sometimes T3 are high (American Thyroid Association guidelines). If you want a refresher on those numbers, our post on reading your thyroid labs walks through them.

Once the labs confirm too much hormone, the next question is why. Your clinician may order thyroid receptor antibodies, which point to Graves disease. Sometimes an imaging study such as a radioactive iodine uptake scan is needed to tell Graves disease from a nodule or thyroiditis. The ATA guidelines describe this stepwise approach.

Blood tests alone can be misleading in a few situations. Biotin supplements can interfere with some lab assays, so tell us if you take them. A mildly low TSH with normal hormone levels is called subclinical hyperthyroidism, and it is managed differently from overt disease.

Treatment options and their tradeoffs

There are three main treatments for Graves disease, and none is the best for everyone. The ATA guidelines lay out all three, and the choice depends on your age, symptoms, other health conditions, pregnancy plans, and preference (ATA guidelines).

Antithyroid medication. Methimazole is the usual first choice. It lowers how much hormone your thyroid makes and is often taken for a year or more. The upside is that it avoids surgery or radiation. The downside is that the condition can come back after you stop, and rare side effects such as a drop in white blood cells or liver problems mean you need to know which symptoms to report right away, such as fever or a sore throat. Propylthiouracil is used less often because of a higher liver risk, though it still has a role in early pregnancy.

Radioactive iodine. This is a pill that gradually shrinks the overactive thyroid tissue. It is effective, but many people end up with an underactive thyroid afterward and need lifelong thyroid hormone replacement. It is generally avoided in pregnancy, and people with active eye disease need a careful discussion first.

Surgery. Removing the thyroid gives the most definitive result and is often chosen for large goiters, suspicious nodules, or when other options are not suitable. It also leads to lifelong thyroid hormone replacement, and it carries surgical risks that depend on the surgeon's experience.

While the thyroid is being brought under control, a beta blocker such as propranolol can ease the racing heart, tremor, and anxiety within hours. It treats symptoms, not the cause.

The eyes need attention

A meaningful share of people with Graves disease develop thyroid eye disease, where the tissue around the eyes becomes inflamed. Signs include gritty or dry eyes, redness, swelling, double vision, and a bulging look. Smoking raises the risk and can make eye disease worse, so quitting is one of the most useful steps you can take (Smith and Hegedus, NEJM 2016).

Eye symptoms deserve an ophthalmology referral, ideally one familiar with thyroid eye disease. A newer medicine, teprotumumab, reduced eye bulging in a randomized trial of people with active thyroid eye disease (Douglas et al., NEJM 2020). It is a specialist treatment with its own side effects, so it is not a first stop for everyone.

What telehealth can and cannot do

Much of hyperthyroidism care fits well into telehealth. We review your symptoms, order labs you can complete at a lab near you, interpret results, start and adjust medication, and recheck levels every few weeks while your dose is tuned. Follow-up visits are often quick and easy to schedule.

Some steps happen elsewhere. A hands-on neck exam, an uptake scan, radioactive iodine treatment, thyroid surgery, and a full eye exam all need a local specialist. We coordinate those referrals so you are not left to sort them out alone.

When to get checked

See a clinician soon if you have a persistent fast heartbeat, unexplained weight loss, tremor, or heat intolerance, especially with a family history of thyroid disease. Seek urgent care for chest pain, fainting, a very high fever with a racing heart, or confusion. These can signal a rare but serious flare of thyroid hormone called thyroid storm.

Next steps

If you suspect an overactive thyroid, or you have been told your TSH is low and nobody explained what comes next, we can help you sort it out. Visit our endocrinology page to book a telehealth visit. Most major plans are accepted, including Medicare. Primary care should not be something you buy on top of the coverage you already pay for.