Radioactive Iodine Therapy (RAI)
Radioactive Iodine Therapy (RAI) is a targeted treatment that uses radioactive iodine to selectively destroy overactive or cancerous thyroid cells while minimizing effects on the rest of the body. It is a highly effective option for treating conditions like hyperthyroidism and thyroid cancer, though it often requires long-term management of hypothyroidism as a result.
My RAI Therapy Journey
Once I was diagnosed with hyperthyroidism, I scheduled an RAI therapy appointment - but then canceled it. I decided to try homeopathy and an anti-inflammatory diet instead. While these did help with the symptoms, they didn’t improve my thyroid condition (those numbers actually got worse). So after the few months I had set aside - I made the decision to proceed with RAI (Radioactive Iodine) therapy.
Scheduling the appointment was a big step. I'm nervous. I knew I was about to lose a part of my body, and it wasn’t a decision I made lightly. On the day of the appointment, as the tech is discussing the precautions, it hit me when I saw the lead container holding the pill. It’s designed to contain the radiation, that’s when I thought: I’m about to become radioactive. What if I forget something? What if I make my husband or dog sick? I can’t even remember things as it is.
I took the pill, it was smallish, grey and easy to swallow. We went home and I had to figure out how to keep my dog away from me - he's my shadow - I think this was the hardest part.
I felt okay overall, with only mild nausea and a slight headache. By day 4 after RAI therapy, I began experiencing a loss of taste (even water) and most foods had an strange flavor. The loss of taste didn't last long.
My memory is still somewhat iffy, but on a good note, my heart wasn't racing, finally giving up its dream of qualifying for the Indy 500.
What Happens After Taking the Radioactive Iodine Pill?
Ingesting RAI
After ingesting the radioactive iodine (I-131), the thyroid gland absorbs it, as it does with regular iodine. The radioactive iodine emits radiation, destroying overactive or cancerous thyroid cells while sparing most of the rest of your body.
Immediate Precautions
- Radiation Safety: You’ll emit small amounts of radiation for a few days to a week. Doctors will provide specific precautions, such as maintaining distance from others, especially children and pregnant women, and avoiding sharing items like utensils or towels.
- Hygiene: Frequent hand washing, flushing the toilet twice, and showering regularly are usually recommended.
Symptoms After Treatment
You may or may not experience side effects such as:
- Sore throat
- Neck tenderness
- Swelling
- Salivary gland swelling or dryness
- Dry eyes or vision changes
- Nausea
In some cases, hyperthyroid symptoms like anxiety or a rapid heart rate can temporarily worsen as the destruction of thyroid cells releases stored hormones. Mild nausea or dry mouth may also occur but generally resolve quickly.
Loss of Taste
Another potential side effect of RAI therapy is a temporary loss or alteration of taste. This happens because the radioactive iodine may affect the salivary glands near the thyroid, leading to less saliva production, also known as "dry mouth." You might notice food tastes different, metallic, or bitter, or that you can’t taste as well as before. This can be frustrating but it usually gets better over time. Drinking plenty of water, sucking on sour candies, and talking to your doctor can help manage this issue.
I lost my sense of taste (and smell) and it was so weird when even water tasted terrible (and that's about all I drink these days) - it was definitely frustrating.
Why Am I Cramping After RAI Therapy?
Muscle cramps are a common complaint after treatment for Graves’ disease or after radioactive iodine therapy. This usually happens when the thyroid slows down too much - leading to hypothyroidism. But there are a few other reasons cramps can sneak in, too.
This happened to me - and let me tell you, the cramping was no joke. I had cramps in places I didn’t even know could cramp. The cramping was so intense and downright miserable.
Low Thyroid Hormone Levels (Hypothyroidism)
- After RAI, the thyroid may not produce enough hormone.
- This slows muscle metabolism, weakens muscles, and causes cramping, fatigue, and stiffness.
- Even small imbalances in your levothyroxine dosage can lead to muscle symptoms.
Calcium or Magnesium Imbalance
- RAI can sometimes affect the parathyroid glands, leading to low calcium levels.
- Low magnesium is also common and often overlooked - this can trigger cramping on its own.
- Supplementing with magnesium glycinate or citrate (200–400 mg/day) can help, and these forms are gentle on the stomach.
Potassium and Sodium Imbalance
- Changes in thyroid hormone levels affect how your body holds onto potassium and sodium.
- Electrolyte imbalances like low potassium (hypokalemia) can contribute to muscle cramps, though it’s less common than magnesium or calcium issues.
Dehydration and Poor Circulation
- Hypothyroidism can lead to fluid retention or shifts, which reduce circulation to muscles.
- Reduced blood flow = less oxygen and nutrients to your muscles = cramping and fatigue.
Nerve Involvement
- Hypothyroidism can affect the nervous system, slowing nerve signals and increasing nerve sensitivity - this can feel like twitching or cramping.
- Sometimes, tingling, numbness, or pins-and-needles accompany cramps if nerves are involved.
What Can You Do About Cramping
Check Thyroid Hormone Levels
- Regularly test TSH, Free T4, and sometimes Free T3 to make sure your dosage is working.
- Even small adjustments in medication can make a big difference.
Monitor Electrolytes
- Ask your doctor to check calcium, magnesium, and potassium levels.
- Supplement as needed:
- Magnesium: Glycinate or citrate is best (200–400 mg/day).
- Calcium: From food or supplements, especially if your parathyroids were affected.
Stay Hydrated
- Drink at least 8–10 cups of water daily, especially if you sweat a lot or take diuretics.
- Dehydration worsens electrolyte imbalance and circulation.
Eat a Cramp Busting Diet
- Magnesium-rich foods: Spinach, pumpkin seeds, almonds, avocados, bananas.
- Calcium-rich foods: Yogurt, leafy greens, fortified almond milk.
- Potassium-rich foods: Bananas, sweet potatoes, beans, avocados, salmon.
Gentle Movement
- Do light stretches, gentle yoga, or walking daily.
- This improves circulation and keeps muscles from stiffening up.
Use Heat Therapy
- Soak in a warm bath with Epsom salts (magnesium sulfate).
- Use a heating pad on tense or cramping areas.
Be sure to discuss any muscle cramps with your thyroid healthcare provider - they can help determine if it’s related to your hormone levels or something else.
Will a Person Develop Hypothyroidism?
Yes, hypothyroidism is a common and often expected outcome of RAI therapy. This is especially true for patients with hyperthyroidism caused by conditions like Graves disease or for those treated for thyroid cancer. The purpose of RAI therapy is to destroy enough thyroid tissue to halt excessive hormone production, but this frequently results in the thyroid gland being unable to produce adequate hormones, leading to hypothyroidism.
Hypothyroidism may develop within weeks to months after treatment. Regular blood tests to monitor thyroid hormone levels (TSH, T3, and T4) are essential during this time to detect and manage the condition early.
Why Hypothyroidism Happens
Radioactive iodine therapy often intentionally destroys most, if not all, of the thyroid gland to stop overactive or cancerous processes. Without enough functional thyroid tissue, the gland cannot maintain normal hormone production, necessitating external hormone replacement.
Managing Hypothyroidism
Managing hypothyroidism involves restoring and maintaining normal thyroid hormone levels through consistent treatment and ongoing monitoring, ensuring optimal health and well-being.
Thyroid Hormone Replacement Therapy
When hypothyroidism develops, doctors typically prescribe levothyroxine, a synthetic thyroid hormone, to restore normal hormone levels. This medication is carefully dosed based on blood tests and symptoms, and adjustments may be needed periodically.
Ongoing Monitoring
Regular follow-ups to assess thyroid hormone levels ensure proper treatment and long-term well-being. Most individuals achieve a stable dose of hormone replacement therapy, enabling them to maintain a healthy and active lifestyle.
Lifestyle After Radioactive Iodine (RAI) Therapy
- With appropriate hormone replacement and monitoring, most individuals live a normal, healthy life post therapy.
- Early detection and management of hypothyroidism are key to avoiding complications like weight gain, fatigue, or cardiovascular issues.
Radioactive Iodine Therapy is a highly effective treatment for many thyroid conditions, but it requires long-term commitment to monitoring and potentially managing hypothyroidism. Discussing your concerns and expectations with your healthcare provider is essential to ensure the best outcomes.
