Thyroid Eye Disease (TED) isn’t just about dry eyes or puffy eyelids. It’s an autoimmune condition that attacks the tissue behind your eyes, causing swelling, pain, and sometimes vision loss. If you’ve been diagnosed with Graves’ disease-or even if your thyroid levels are normal-you could still be at risk. About half of people with Graves’ develop TED, and it can happen at any point, even years after thyroid treatment. The good news? We now have better tools than ever to stop it before it causes permanent damage.

What Does Thyroid Eye Disease Actually Feel Like?

Most people don’t realize TED starts subtly. You might think it’s allergies or tired eyes. But if you’re getting a gritty, sandy feeling in your eyes-especially when blinking-or if your eyelids feel swollen or red, that’s a red flag. Light sensitivity is common, too. You might find yourself wearing sunglasses indoors. Pain behind the eyes, especially when you move them, is another key sign. About 52% of patients report this.

Forward bulging of the eyes (proptosis) affects about 31% of people with moderate-to-severe TED. Double vision isn’t rare either-it shows up in nearly 1 in 4 cases. These symptoms usually hit both eyes, though 11% of people have them in just one. The worst part? These aren’t just cosmetic. When the muscles behind the eye swell, they press on the optic nerve. That’s when vision loss becomes a real risk.

Doctors use something called the Clinical Activity Score (CAS) to measure how active the disease is. A score of 3 or higher means inflammation is still going strong-and that’s the window to act. Once the inflammation settles, the damage can become permanent. That’s why timing matters more than you think.

Why Steroids Are Still the First Line of Defense

For decades, steroids have been the go-to treatment for active TED. The goal isn’t to cure it-it’s to calm the immune system before it destroys eye tissue. The most effective method? Intravenous (IV) methylprednisolone. This isn’t your typical oral pill. It’s given as a high-dose infusion once a week, usually for 12 weeks total: 500 mg for six weeks, then 250 mg for six more.

Studies show this approach works in 60 to 70% of patients. It reduces swelling, eases pain, and improves double vision. But it’s not without risks. About 18% of people develop glucose intolerance-some even get prediabetes. Weight gain is common, averaging 8.2 kg. Osteoporosis is a concern for long-term users. That’s why doctors limit the total dose to 4.5-5.0 grams to protect the liver.

Oral prednisone is cheaper and easier to get, but it’s less effective and harder to tolerate. About 25-30% of patients relapse after stopping it. Plus, the side effects hit harder and faster. For most people with moderate-to-severe TED, IV steroids are still the standard. But they’re not the whole story.

The Biologic Revolution: Teprotumumab Changes Everything

In 2020, the FDA approved teprotumumab (Tepezza®), and everything changed. This isn’t just another steroid. It’s a targeted therapy that blocks the IGF-1 receptor-the exact protein driving inflammation in TED. For the first time, we’re treating the root cause, not just the symptoms.

The OPTIC trial showed staggering results: 71% of patients had a 2 mm or greater reduction in eye bulging after eight infusions, compared to just 20% on placebo. Double vision improved in 59% of those on teprotumumab versus 26% on placebo. These aren’t small gains-they’re life-changing. One patient in Glasgow reduced her proptosis from 24mm to 20mm after treatment. She could finally drive again without double vision.

The treatment schedule is simple: eight infusions, given every three weeks. But the cost? It’s brutal. In the U.S., a full course runs around $360,000. Even with insurance, many patients face $5,000 per infusion. Insurance denials are common-42% of patients report delays or rejections. In the UK, access is better but still uneven. NHS approval can take months, and not all hospitals offer it.

Side effects? Muscle spasms (24%), hearing changes (11%), and high blood sugar (8%) are the most common. The FDA added a boxed warning for these in 2021. But for many, these are worth it compared to the long-term damage steroids can cause.

What About Other Biologics?

Teprotumumab isn’t the only option on the horizon. Satralizumab (Enspryng®), approved in 2023, is a subcutaneous injection that blocks IL-6, another key player in TED inflammation. Early data shows a 54% response rate for eye bulging. It’s easier to administer than IV infusions and may be cheaper long-term.

Rituximab and tocilizumab have been tried too, but the evidence is weaker. They’re used mostly when teprotumumab fails or isn’t available. A new trial in the UK called TOPAZ is testing whether adding selenium to teprotumumab boosts results. Early numbers show an 82% response rate-higher than either treatment alone.

The market is shifting fast. Amgen bought Horizon Therapeutics in 2023 for $28 billion, mostly because of Tepezza’s $2.1 billion in 2022 sales. A biosimilar version is expected by 2025, which could cut costs by 30-40%. That could make treatment accessible to far more people.

When Surgery Comes In-and When It Doesn’t

Surgery isn’t the first step. It’s the last. Orbital decompression, eye muscle surgery, and eyelid surgery are only done after the disease has been inactive for at least 6 months. That’s because if you operate while inflammation is still active, you risk making things worse.

Decompression surgery removes bone behind the eye to create space, reducing bulging by 2-5 mm. But 15% of patients develop new or worse double vision afterward. Sinus infections happen in 8%, and vision loss-though rare-is still a risk at 0.5%. Strabismus surgery fixes misaligned eyes, but only if muscle movement is limited by less than 15 prism diopters. Beyond that, it’s unreliable.

Prisms in glasses help 60% of people with double vision. But they’re a band-aid. If the muscles are too stiff or swollen, prisms won’t work. That’s why treating the inflammation early is so critical. You don’t want to end up needing surgery just because you waited too long.

What You Can Do Right Now

If you suspect TED, don’t wait. See an endocrinologist and an ophthalmologist who specialize in thyroid eye disease. Get a CT or MRI scan to check for muscle enlargement. Test your TRAb levels-if they’re above 15 IU/L, your risk is high.

Stop smoking. It’s the biggest modifiable risk factor. Smokers are nearly eight times more likely to develop severe TED. Even if you’ve smoked for years, quitting now can still reduce your risk of progression.

For mild cases, preservative-free artificial tears help. Selenium supplements (200 mcg daily) show modest benefits-about a 23% improvement in quality of life, according to Cochrane. It’s not a cure, but it’s safe and cheap.

And if you have moderate-to-severe disease? Don’t delay. Start treatment within two weeks of symptoms. Every week you wait lowers your chance of a full recovery. IV steroids or teprotumumab can prevent blindness, double vision, and permanent disfigurement.

What’s Next for TED Treatment?

The future is personalized. Researchers are looking at genetic markers that predict who’s most likely to develop TED and who will respond best to which drug. Within five years, we may be able to test your DNA and know whether you need biologics, steroids, or just watchful waiting.

Long-term data is still limited. The OPTIC trial’s 4-year follow-up results are expected in mid-2024. We need to know if teprotumumab’s benefits last-or if the disease comes back. But for now, it’s the most effective treatment we’ve ever had.

Thyroid Eye Disease used to be something you lived with. Now, it’s something you can treat-before it changes your life forever. The tools are here. The question is: are you getting the right care at the right time?