Erin Moriarty Has Graves' Disease. What to Know About the Condition

Time​ Magazine

16-06-2025

Erin Moriarty—an actress known for her role as Annie January on the Amazon Prime Video show The Boys —recently announced on Instagram that she has Graves' disease. While Moriarty, 30, didn't share exactly what led to her diagnosis, she noted that she initially brushed off her symptoms: 'If I hadn't chalked it all up to stress and fatigue, I would've caught this sooner,' she wrote, urging her followers to pay close attention to their own health. 'Don't 'suck it up' and transcend suffering; you deserve to be comfy.'
What exactly is Graves' disease? We asked experts how the condition shows up and what managing it looks like.
What is Graves' disease?
Graves' disease—which affects about 1% of people in the U.S.—is an autoimmune disorder that occurs when the thyroid gland produces too much thyroid hormone. 'Your immune system attacks your thyroid gland and causes it to overproduce thyroid hormone, which we all need at normal amounts,' says Dr. Stelios Mantis, an endocrinologist at Rush University System for Health. 'But at excessive amounts—which is what happens when it's being overproduced in Graves disease—it can cause some ill effects.'
Patients often ask Dr. Ossama Lashin, medical director of the thyroid center at the Cleveland Clinic, why they got Graves' disease. Research suggests there's a genetic predisposition; there are also environmental factors that could play a role, including a history of certain viral or bacterial infections (like Epstein–Barr virus), having too much or little iodine, and some medications. Gender makes a difference, too: 'It's more prevalent in women—five to 10 times more common, depending which studies you're referring to,' he says. And while it can show up at any age, people are often diagnosed in their 30s to 50s.
What kind of symptoms can it cause?
When people have too much thyroid hormone, it makes everything in their body 'go fast,' says Dr. Charit Taneja, an endocrinologist with Northwell Health. 'People will come in with heart palpitations or feeling like their heart is beating really fast,' he says. 'They might be shaking or trembling, or feeling restless and anxious'—sometimes to the point that they can't sleep at night. Patients often describe feeling unusually hot and sweating excessively. They also might have unintentionally dropped pounds, even though they're so hungry that they're eating more than usual, because their overactive thyroid is causing their body to burn a lot of calories.
'It's hard to miss—the majority of patients feel that something is wrong, like, 'This is not me,'' Lashin says. ''I can't sleep, my heart is racing, I'm sweating a lot, I'm losing weight for no reason, and I haven't changed anything.'' People with an overactive thyroid tend to seek care 'sooner than somebody with an under-active thyroid, where it wouldn't have such marked symptoms."
There might be physical changes, too. Some people develop an enlarged thyroid in their neck, also called a goiter. 'The gland may grow in size, so people may notice swelling at the bottom part of their neck,' Lashin says. 'That doesn't happen for everybody, and it happens at varying degrees.'
That's a sentiment Moriarty echoed in her post. 'Autoimmune disease manifests differently in everybody/every body,' she wrote. 'Your experience will be different from mine. My experience will be different from yours. Perhaps greatly, perhaps minutely.'
How is Graves' disease diagnosed?
Graves' is typically diagnosed through a combination of blood tests, a physical exam, and, occasionally, a thyroid scan. Doctors look for low thyroid-stimulating hormone (TSH) levels and high thyroid hormone levels (T3 and T4). 'The slam-dunk one would be thyroid-stimulating antibodies'—like thyroid-stimulating immunoglobulin, or TSIs—'being positive,' Mantis says.
Some patients undergo a radioactive iodine uptake and scan, which can definitively diagnose Graves' disease. But it's more invasive, he adds, and not always necessary. Most doctors rely on blood work and a 'good, thorough physical exam' to determine that someone has Graves'.
A rare but serious complication
About 1 in 3 people with Graves' disease develop eye problems, and in the most serious cases, that can mean thyroid eye disease. Though it's commonly associated with Graves' disease, it can also occur with other autoimmune diseases when the immune system mistakenly attacks the soft tissue behind the eyes, leading to inflammation and bulging of the eye.
'It's very visible,' Taneja says. 'We call it proptosis, meaning your eyes are bulging forward. It's disheartening when it happens, but it is something that does happen with Graves' disease.'
Patients often tell Lashin that their eyes look different, so he asks them for an old picture or an old driver's license. When they compare them, the change can be striking. Other times, family members point out the change, he says.
Thyroid eye disease can also be painful. 'There's dryness, and a sort of grittiness, like a sand-like sensation in your eyes,' Taneja says. 'Some people will complain of excessive tearing.'
Thyroid eye disease is challenging to treat, but there are newer medications that can make a difference, he adds. Even people with Graves disease who don't have eye troubles are typically encouraged to routinely see an ophthalmologist to ensure they don't develop any complications.
A 'thyroid storm'
Untreated or poorly controlled Graves' disease can lead to a 'thyroid storm,' which is a rare but potentially life-threatening complication. It happens when thyroid hormone levels increase rapidly, causing heart rate, blood pressure, and body temperature to soar. 'The person is burning a lot of calories, breaking down a lot of tissue, and producing a lot of heat, and all these things can progress to a point where the body systems cannot compensate for that stress anymore,' Lashin says. 'It's a serious condition that requires intensive care treatment' in the hospital, often including antithyroid medications, iodine solution, cooling blankets, and respiratory treatment.
How is Graves' disease treated?
When someone is diagnosed with Graves' disease, they typically start a daily medication called methimazole, which helps reduce the thyroid gland's production of hormones. Some also take beta-blockers to manage symptoms like a rapid heart rate and tremors. While Moriarty didn't divulge her treatment plan, she did note that her regimen helped her feel better right away: 'Within 24 hours of beginning treatment, I felt the light coming back on,' she wrote on Instagram. 'It's been increasing in strength ever since.'
That's a common experience, Taneja says. 'People tend to feel better pretty quickly,' he says. 'The anxiety gets better, the heart-racing gets better, and some people who've lost a bunch of weight unintentionally will start gaining that weight back.'
Most people stay on oral medication for at least 1.5 to two years, and some do so well that they achieve remission. 'I would say there's like a 50% chance that people will come off the medications,' Taneja says. 'Then there's the other half that need more prolonged treatment, and it's hard to predict how long they might need it for.' In more advanced cases, he adds, patients might eventually require another type of treatment: either radioactive iodine therapy, which destroys thyroid cells, or surgery to remove all or part of the thyroid gland.
Mantis hopes that Moriarty's post about Graves' disease will encourage people to take their own symptoms seriously, even if they're vague, easy to write off as run-of-the-mill stress, or feel too random to be related. 'It's important to listen to your body,' he says. 'If something doesn't feel right, talk to your provider.'