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Eye problems are common in hyperthyroidism, a condition where your body has too much thyroid hormone. People can get Graves' ophthalmopathy, also known as thyroid eye disease (TED) when the condition is unaddressed. But eye problems are not just restricted to people with hyperthyroidism. People with hypothyroidism can also experience eye issues. Eye issues associated with hypothyroidism may even be a side effect of common thyroid medications used to treat an underactive thyroid. Here's what you should know if you struggle with eye problems and are treating your hypothyroidism with Synthroid.
The thyroid is a small, butterfly-shaped gland at the base of your neck. As part of the endocrine system, the thyroid gland produces hormones that regulate your body's energy use, along with many other important functions. When thyroid hormone levels are unbalanced, body processes change, affecting virtually every system in the body.
Researchers don't quite understand why thyroid disease can affect your eyes. However, since there are thyroid hormone receptors all over our bodies, it stands to reason that thyroid diseases can affect every organ system.
Common eye complaints in hyperthyroidism
Hyperthyroidism is a condition in which the thyroid gland produces too much thyroid hormone. Signs and symptoms vary from person to person but commonly include irritability, sleeping problems, muscle weakness, fast heartbeat, heat intolerance, tremors, or weight loss. Graves' disease, an autoimmune condition, causes more than half of the cases of hyperthyroidism in the United States.
People with hyperthyroidism can have a variety of concerning eye symptoms, including:
- Bulging eyes
- A gritty or sandy feeling
- Pressure or pain
- Redness or inflammation
- Puffiness and retracted eyelids
- Light sensitivity
- Double vision, and
- Vision loss
One of the hallmark signs of Graves' ophthalmopathy is bulging eyes. Not everyone with Graves' disease will develop this symptom (only about 30%). Still, vision changes can be hard to restore even with treatment.
Common eye complaints in hypothyroidism
As seen above, we know eye problems are common in people with an overactive thyroid. However, people with an underactive thyroid may also be at risk for eye troubles, although it is less common and is usually only seen in people with Hashimoto's.
The condition of an underactive thyroid is hypothyroidism. when the thyroid gland does not produce enough thyroid hormones. Signs and symptoms vary from person to person but commonly include cold intolerance, fatigue, constipation, slow heart rate, low mood, and weight gain. Globally, the most common cause of hypothyroidism is too little iodine. However, in iodine-sufficient countries like the United States, the most common cause of hypothyroidism is Hashimoto's disease. Hashimoto's disease is an autoimmune thyroid disease that causes the immune system to mistakenly attack the thyroid gland.
Common eye complaints in people with Hashimoto's include:
- Dry eyes
- Blurry vision
- Eyelid abnormalities (like upper eyelid retraction)
- Swelling around the eyes
- Thinning eyebrows and eyelashes
Blurred vision is one of the most common complaints of hypothyroid patients. Blurry vision may occur because pressure from swelling could apply pressure on the optic nerve.
Dry eyes are also a frequent problem for people with Hashimoto's disease. Interestingly, the tear ducts are a target organ in the eye for thyroid hormone. When there isn't enough thyroid hormone circulating, these ducts cannot make enough lubrication to keep your eyes comfortable.
There are several symptoms associated with dry eyes. For example, you may have:
- Eye irritation
- Excess tearing (seems counterintuitive, but that is a hallmark sign!)
- Blurred vision
- Redness, and
Synthroid is one of the most common medications used to treat hypothyroidism. Also known by its generic name levothyroxine, Synthroid contains synthetic thyroid hormone that helps to replace low thyroid hormone in your body.
Like most medications, Synthroid comes with a list of side effects. One of the rarer side effects of Synthroid is that it may cause blurred or double vision and eye pain. These symptoms may stem from swelling caused by taking too much thyroid hormone or an adverse reaction to the medication, like an allergic reaction.
There are very few reports that Synthroid directly causes eye problems, except in rare cases where it is an adverse reaction. If you struggle with eye issues while taking Synthroid, it is more likely related to your thyroid not being correctly managed or other causative factors like allergies, etc.
Discontinuing the use of your Synthroid thyroid medication won't cause withdrawal symptoms. However, discontinuing the use of your Synthroid thyroid medication may cause you to experience some of the symptoms of hypothyroidism that it is working to treat. This resurgence of symptoms occurs because Synthroid was delivering thyroid hormones to your body, but when you stop the drug, your body no longer receives the necessary hormones.
If you have questions about stopping treatment with Synthroid, we recommend that you first talk with your thyroid doctor.
If you experience vision changes while taking Synthroid, it is important to consult your healthcare provider. Ideally, you will see an improvement in your vision if you had eye problems like dryness before starting to take Synthroid. But, if you have eye changes, it is essential to check your thyroid function with a thyroid blood test and consult your thyroid doctor to optimize your treatment.
Aside from checking in with your thyroid doctor, here are some other steps to keep your eyes healthy:
See your eye doctor
Regular eye exams are necessary to check for changes in your vision and eye anatomy. However, your eye doctor can also help you with eye problems related to other health conditions. Your eye doctor will likely be up-to-date on how best to diagnose and treat frustrating eye problems like dryness and excess tearing.
Try over-the-counter eye medications
If you suffer from dry eyes or allergic eye symptoms, there are plenty of over-the-counter options to keep your eyes more comfortable. You can find eye drops in preservative and non-preservative forms that usually work well to lubricate the eyes. You may also run across ointments, but they can blur your vision.
Eye doctors will usually rely on over-the-counter remedies first if they think they will be helpful. However, there are times when prescription eye medication may be more beneficial. If you suffer from inflammation, you will likely need an anti-inflammatory eye drop to help decrease swelling.
Consider natural treatments
Warm, wet compresses and gentle tear duct massaging are extremely useful tools for boosting moisture in the eyes. A diet rich in omega-3's may also help hydrate your eyes, so make sure to eat plenty of nuts, seeds, salmon, and other fatty fish.