Understanding Radioactive Iodine Treatment for Thyroid Cancer

Radioactive iodine therapy is an important treatment for thyroid cancer that helps eliminate any remaining thyroid tissue or cancer cells after surgery. This treatment involves taking radioactive iodine orally, which specifically targets thyroid cells. It has been proven effective in treating thyroid cancer and reducing the risk of recurrence.

The success of your treatment depends on careful preparation and following specific guidelines. This guide by the department of Nuclear Medicine and Molecular Imaging will help you understand what to do before and after your treatment to ensure the best possible outcome.

Before Your Treatment

Medication Requirements:

• If prescribed Thyrogen: Receive injections 2 days and 1 day before treatment
• Stop thyroxine tablets for 4 weeks
• Take Liothyronine (T3) as prescribed by your doctor, if applicable

Dietary Restrictions (2 weeks before and 3 days after treatment):

• Avoid:
  • Seafood (fish, sushi, shellfish, kelp, seaweed)
  • Iodine-containing vitamins or supplements
  • Dairy products (milk, chocolate, ice cream, cheese, yoghurt, butter)
  • Egg yolks or foods containing whole eggs
  • Soy products (sauce, milk, tofu)
• Limit salt intake
• Avoid topical iodine applications

On Treatment Day:

• No food or drink 2 hours before and after treatment (plain water allowed)

After Your Treatment

Immediate Care:

• Drink 2-3 litres of fluid daily for 3 days (unless otherwise advised)

First 2 Days After Discharge:

• Avoid crowded places (can return to work when feeling well)
• Sleep separately from adults and avoid intimacy
• Maintain arm's length distance from pregnant women and children under 12

For One Week:

• Sit while urinating (including men)
• Flush toilet twice after use
• Use separate utensils and wash clothes separately
• Clean shared telephone mouthpieces after use

Extended Precautions:

• Sleep separately from pregnant women and children under 12:
  • For ≤100 mCi dose: 1 week
  • For >100 mCi dose: 3 weeks
• Avoid prolonged public transport (over 2 hours) for 1 week
• Carry discharge note when travelling (4 weeks)

Special Considerations

For Female Patients:

• Confirm you are not pregnant before treatment
• Avoid pregnancy for 6 months after treatment
• Stop breastfeeding until next pregnancy

For Male Patients:

• Avoid impregnating partner for 4 months after treatment

Travel Requirements:

• Request a medical memo if travelling overseas post-treatment
• Keep discharge note with you for 4 weeks when travelling

Additional Resources

Our patient information leaflets are available for download:
Thyroid Cancer (Eng).pdf
Thyroid Cancer (Chi).pdf