Hyperthyroidism: Should I use antithyroid medication or radioactive iodine?
- Get the facts
- Compare your options
- What matters most to you?
- Where are you leaning now?
- What else do you need to make your decision?
1. Get the Facts
Your options
- Take radioactive iodine. It destroys part or all of the thyroid gland.
- Take antithyroid medicine. It lowers the amount of thyroid hormone in your body.
Graves' disease is the most common cause of hyperthyroidism. If your hyperthyroidism is not caused by Graves' disease, this information may not apply to you.
Key points to remember
- Most people will be cured of hyperthyroidism after one dose of radioactive iodine. The radioactivity in the iodine kills most or all of your thyroid gland. This usually leads to hypothyroidism, which means that your body makes too little thyroid hormone. When you have hypothyroidism, you need to take thyroid hormone medicine for the rest of your life.
- If you are pregnant or want to get pregnant within 6 months of treatment, or if you are breast-feeding, you cannot use radioactive iodine.
- You can use radioactive iodine after you have been treated with antithyroid medicine.
- Radioactive iodine is often recommended if you have Graves' disease and are older than 50, or if you have thyroid nodules that are releasing too much thyroid hormone.
- Antithyroid medicine works best if you have only mild hyperthyroidism. It may also be a good choice if this is the first time you are being treated for Graves' disease, if you are younger than 50, or if your thyroid gland is only swollen a little bit (small goiter).
- Antithyroid medicine does not damage your thyroid gland. But it doesn't work for everyone, and you may have a relapse.
- If you have used antithyroid medicine and you have a relapse, taking antithyroid medicine again may not work.
FAQs
What is hyperthyroidism?
When you have hyperthyroidism, your thyroid gland makes too much thyroid hormone. Thyroid hormones control your metabolism—how your body turns food into energy—and they influence your heart rate, digestion, muscle and bone strength, and cholesterol levels.
When you have too much thyroid hormone, all of your body's functions speed up.
What are the risks of hyperthyroidism?
Without treatment, hyperthyroidism can lead to:
- Heart problems.
- Bone problems.
- Thyroid storm. This is a life-threatening condition that occurs when the thyroid releases a lot of thyroid hormone in a short time.
Why might your doctor recommend one treatment over the other?
Your doctor may recommend radioactive iodine if:
- You have Graves' disease and you are older than 50.
- You have thyroid nodules that are releasing too much thyroid hormone.
- You have taken antithyroid medicine before and have had a relapse.
Your doctor may recommend antithyroid medicine if:
- Your hyperthyroidism is mild.
- Your thyroid gland is only swollen a little bit (small goiter).
- You are younger than 50 and this is the first time you are being treated for Graves' disease.
- You are pregnant, want to become pregnant within 6 months of treatment, or are breast-feeding.
2. Compare Options
Radioactive iodine Antithyroid medicine What is usually involved?
- You swallow one liquid dose of this medicine.
- Your symptoms start to go away in 8 to 12 weeks.
- You will take thyroid hormone medicine for the rest of your life.
- You take this medicine every day for 1 to 2 years.
- If it works, your symptoms start to go away in 1 to 8 weeks. Your thyroid hormone levels will stay in the normal range even after you stop taking this medicine.
- If it doesn't work, you can choose to take radioactive iodine.
What are the benefits?
- Most people are cured after one dose.
- Studies have shown that medicine permanently lowers thyroid levels in up to half of people who use it.1
- The medicine may reduce your risk of getting thyroid eye disease.
What are the risks and side effects?
- Side effects include an inflamed thyroid gland.
- Hypothyroidism (having too little thyroid hormone) usually develops within 1 to 10 years. Because of this, you will have to take thyroid hormone medicine for the rest of your life.
- This treatment may make thyroid eye disease worse for a while.
- Side effects include rash, itching, joint aches, liver problems, and being less able to fight infection because of a low white blood cell count.
- Medicine doesn't work for everyone. Relapses are common.
Personal stories
Are you interested in what others decided to do? Many people have faced this decision. These personal stories may help you decide.
If you need more information, see the topic Hyperthyroidism.
Personal stories about treatment for hyperthyroidism
These stories are based on information gathered from health professionals and people who have had hyperthyroidism. They may be helpful as you make important health decisions.
"Who would have thought that the symptoms I was having were caused by my thyroid gland? I thought that they were just part of growing older. But after I decided to pay attention and wrote down how I felt and told my nurse practitioner, she did blood tests that showed that I had an overactive thyroid gland. Then she referred me to a doctor for treatment. I have never been a guy who liked to take medicine, so I opted to take radioactive iodine. I like the idea that I only had to take it once and then it was over and done with. Now I take thyroid hormone every day. But it’s easy to take, and I just see my doctor once or twice a year for monitoring."
— Harry, age 63
"Some people tell me that taking radioactive iodine is the best treatment for my thyroid condition. But I don't like the idea of taking something that's radioactive. Maybe I am too cautious. My doctor tells me that the amount of radioactive iodine is so small that it doesn't cause problems. I just can't get past that word "radioactive." I have decided to take antithyroid pills. I don't think I'll have a problem with them. I have a pretty regular kind of life and take vitamins every day, so remembering to take another pill won't make a big difference to me."
— Jesse, age 52
"I took antithyroid medicine for my overactive thyroid about 2 years ago. I had trouble remembering to take the pills every day, and sometimes when I would go out of town to visit my family, I would forget to take my pills with me. Now, my thyroid is acting up again. I don't want to mess with pills. I worry that I might get some of those side effects from taking medicine. I have decided to take radioactive iodine. I know that I have a risk of developing hypothyroidism because of this treatment, but I am willing to take thyroid hormone pills if that happens."
— Emilia, age 45
"My neighbor Geraldo took radioactive iodine for his overactive thyroid gland, and his thyroid gland became underactive. So now he has to take thyroid hormones. I guess I'll just skip the radioactive iodine and take pills. Besides, my doctor tells me that because of my age I might even be able to stop taking the pills and never have to take them again. That sounds good to me."
— Penny, age 35
3. Your Feelings
Your personal feelings are just as important as the medical facts. Think about what matters most to you in this decision, and show how you feel about the following statements.
Reasons to take antithyroid medicine
Reasons to take radioactive iodine
I'm worried that radioactive iodine will damage my thyroid and I'll have to take thyroid hormone pills for the rest of my life.
I can live with the damage to my thyroid, because I know I can take thyroid hormone pills to treat it.
I don't mind taking pills for a few years to see if that will fix my thyroid problem.
I want to get my thyroid problem taken care of quickly.
I worry more about putting something radioactive into my body than about side effects of antithyroid medicine.
I worry more about side effects of antithyroid medicine than about putting something radioactive into my body.
My other important reasons:
My other important reasons:
4. Your Decision
Now that you've thought about the facts and your feelings, you may have a general idea of where you stand on this decision. Show which way you are leaning right now.
Taking antithyroid medicine
Taking radioactive iodine
5. Quiz Yourself
Check the facts.
1. Which treatment is more likely to cure hyperthyroidism?
- Antithyroid medicine
- Radioactive iodine
- Both
- I'm not sure
You are right. Most people will be cured after one dose of radioactive iodine. But this treatment isn't for everyone.2. When does antithyroid treatment work best?
- When symptoms are mild
- When symptoms are very bad
- Both
- I'm not sure
You're right. Antithyroid medicine works best if you have only mild hyperthyroidism.3. Which treatment eventually leads to hypothyroidism (having too little thyroid hormone) in most people?
- Antithyroid medicine
- Radioactive iodine
- Both
- I'm not sure
You are right. This treatment works by killing most or all of the tissue in the thyroid gland. Over time, this leads to hypothyroidism in most people, so they need to take thyroid hormone medicine.Decide what's next.
1. Do you understand the options available to you?
- Yes
- No
2. Are you clear about which benefits and side effects matter most to you?
- Yes
- No
3. Do you have enough support and advice from others to make a choice?
- Yes
- No
Certainty.
1. How sure do you feel right now about your decision?
2. Check what you need to do before you make this decision.
- Nothing. I'm ready to take action.
- I want to discuss the options with others.
- I want to learn more about my options.
3. Use the following space to list questions, concerns, and next steps.
| Author: | Caroline Rea, RN, BS, MS | Last Updated: December 3, 2007 |
| Medical Review: | Caroline S. Rhoads, MD - Internal Medicine David C.W. Lau, MD, PhD, FRCPC - Endocrinology & Metabolism | |
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