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Thyroid eye disease (Graves' orbitopathy): symptoms, smoking and treatment

Thyroid eye disease in Graves' disease: symptoms, how common it is, why smoking matters so much, how treatment of the thyroid (carbimazole, radioiodine, surgery) affects the eyes, selenium, steroids, teprotumumab and surgery.

Illustration: an eye-drops bottle, folded reading glasses and a small dish of capsules.

Thyroid eye disease (TED), also called Graves’ orbitopathy, happens when the immune attack behind Graves’ disease also inflames the muscles, fat and tissues around the eyes. It can make eyes gritty, red, puffy or bulging, and sometimes causes double vision. Most cases are mild. The choice of thyroid treatment, and above all smoking, affects how it goes.

Key points

  • How common: about a quarter to 40% of people with Graves’ disease, depending on the source; moderate to severe disease in only 5% to 6%.
  • Smoking: heavy smokers are up to eight times more likely to develop it, and respond worse to treatment.
  • Thyroid treatment matters: carbimazole or methimazole is preferred when eye disease is active; radioiodine can make it worse unless steroids are given.
  • Treatments: lubricating drops, selenium for mild disease, steroids, newer drugs such as teprotumumab, and surgery once it has settled.

Symptoms

The British Thyroid Foundation lists:

  • staring or bulging eyes
  • gritty, dry or watering eyes, and sensitivity to bright light
  • swollen eyelids, new bags under the eyes, red lids and eyes
  • blurred or double vision
  • pain in or behind the eye, especially when looking up, down or sideways

It is often mistaken for hay fever, an allergy or conjunctivitis. Clues that it is TED: it ignores the hay fever season, it does not itch or make the eyes sticky, and it can ache behind the eye or cause double vision.

How common it is, and who gets it

Figures vary: the NHS says about 1 in 4 people with Graves’ disease, and the British Thyroid Foundation about 40%, mostly mild, with only 5% to 6% developing moderate to severe disease. It can appear before, during or after the thyroid problem, and even when thyroid levels are normal. The European EUGOGO guideline lists the risk factors: smoking, thyroid levels that swing up or down, high TSH receptor antibodies, radioactive iodine treatment and high cholesterol.

Smoking is the big one

Without eye symptoms at diagnosis, a non-smoker’s chance of developing TED is under 1 in 10, according to the British Thyroid Foundation. Smoking doubles it, and heavy smoking raises it eightfold. Smokers also respond worse to treatment, though the disadvantage fades soon after stopping. Smoking also lowers the chance that a course of carbimazole cures the thyroid. Stopping is the single most useful step.

How thyroid treatment affects the eyes

  • Antithyroid tablets (Neo-Mercazole, methimazole) are preferred when eye disease is active and moderate to severe, per EUGOGO. In an Italian trial, eye disease worsened in only 3% of people on methimazole.
  • Radioactive iodine made eye disease appear or worsen in 15% in the same trial; a three-month course of prednisone afterwards prevented it. EUGOGO advises low-dose steroid cover if radioiodine is chosen in mild active disease, and the British Thyroid Foundation advises avoiding radioiodine with active TED.
  • Keeping levels steady matters, especially avoiding an underactive phase. Regular blood tests and taking every dose help the eyes.

Treatments for the eyes

Mild disease. Lubricating drops, gels and ointments, used three or four times a day. Selenium 100 micrograms twice daily for six months, which improved quality of life and eye involvement in a placebo-controlled trial of 159 people with mild disease (EUGOGO recommends it mainly where selenium intake is low). Symptoms often get worse for the first 6 to 12 months, then settle; the inflammation can take up to two years to burn out.

Moderate to severe, active disease. Intravenous steroids, which EUGOGO finds more effective and better tolerated than tablets, often combined with mycophenolate. Other options include orbital radiotherapy and further immunosuppressants. The antibody drug teprotumumab reduced eye bulging by at least 2 mm in 83% of patients against 10% on placebo in a trial of 83 people; the British Thyroid Foundation notes such newer drugs are costly and not yet available in most European countries.

After it settles. Surgery can help: orbital decompression to make room behind the eye, eye muscle surgery for double vision, and eyelid surgery. Prisms on glasses can help double vision in the meantime.

Getting help

TED is best managed jointly by an eye specialist and a thyroid specialist. It can also affect confidence and mood; support groups and counselling help many people.

If you are on carbimazole for Graves’ disease, keep it steady: carbimazole is listed by PockDose, Yasabai and VGR Australia. See Graves’ disease and radioactive iodine.

Sources

Checked 15 October 2026.

  1. Thyroid eye disease (patient leaflet) — British Thyroid Foundation
  2. Overactive thyroid (hyperthyroidism), complications — NHS (UK)
  3. The 2021 EUGOGO clinical practice guidelines for the medical management of Graves' orbitopathy (Bartalena et al., 2021) — European Journal of Endocrinology
  4. Selenium and the course of mild Graves' orbitopathy (Marcocci et al., 2011) — New England Journal of Medicine
  5. Teprotumumab for the treatment of active thyroid eye disease (Douglas et al., 2020) — New England Journal of Medicine
  6. Relation between therapy for hyperthyroidism and the course of Graves' ophthalmopathy (Bartalena et al., 1998) — New England Journal of Medicine