A. Common questions about Iodine therapies

1. What are iodine therapies?

Iodine / radio-iodine therapies are one of the treatment modalities used for thyroid cancer and hyperthyroidism. 

The thyroid gland is a butterfly-shaped gland located in the front of your lower neck. It produces hormones that help your body regulate your metabolism. Radioactive iodine therapy acts by destroying the excess thyroid cells in cancer and hyperthyroidism. This therapy is administered by an expert in nuclear medicine.

2. How do they work?

Radioactive iodine therapy is an effective treatment for thyroid cancer and hyperthyroidism. The radioactive iodine is absorbed into the patient’s body and picked up by the thyroid cancer cells, even if they have spread to other parts of the body. This is because only thyroid cells absorb radioactive iodine, leaving healthy cells unharmed.

3. What conditions are they indicated for?

The principle behind the use of RAI is that radioactive iodine is absorbed only by the thyroid gland and thyroid cells. This therapy, therefore, can be used to treat thyroid cancer. And, since RAI collects mainly in thyroid cells, the radiation destroys only the thyroid gland and cells including those that are cancerous, with little effect on healthy, non thyroid cells in your body.

RAI therapy can also be used to ablate the thyroid tissue in order to treat thyroid cancer that has spread to your lymph nodes and other parts of your body. This is usually very effective in cases where the tissue is not accessible by surgery.  

It can also be used in people suffering from papillary or follicular thyroid cancer that has spread to the neck and other parts of your body.

Radioactive iodine is often recommended if you have thyroid cancer, Graves’ disease and are older than 50 years of age. It is also used if you have hyperthyroidism or thyroid nodules that release too much thyroid hormone causing hyperthyroidism

4. Are there any side effects?

In general, Radioactive Iodine (RAI) is a safe and effective treatment. When RAI is used to treat conditions such as thyroid cancer or hyperthyroidism, a common side effect is hypothyroidism (underactive thyroid). Metallic taste in the mouth, nausea, swollen salivary glands, loss of taste and dry mouth are some of the side effects related to radioactive iodine therapy. Lifelong medical follow up is necessary.

5. Where are they available?

Iodine therapy is available in all major Indian cities in large hospitals and centres. Here’s a list of hospitals/centres that provide Iodine therapy in major cities:  


  • Medcare Institute of Diagnostics
  • MPCT Cancer Hospital in Mumbai
  • Kokilaben Dhirubhai Ambani Hospital 
  • Gleneagles Global Hospital, Mumbai


  • Narayana Health, Delhi 
  • MaxHealthcare, Delhi
  • Indraprastha Apollo Hospitals, Delhi


  • Gleneagles Global Hospital, Mumbai 
  • Fortis Hospitals, Bangalore
  • Narayana Health, Bangalore

6. Is it a proven therapy? How long has it been around?

Radioactive iodine has been used to treat hyperthyroidism for more than 60 years. 

A study found that Radioactive iodine treatment is an effective modality for definitive treatment of hyperthyroidism with long-term cure approaching 80%(7). As for Thyroid cancer, another study found that  I-131 provided an effective therapeutic method for well-differentiated thyroid cancer in patients with distant metastasis(8).

7. What are the long-term risks and how can one minimize them?

In general, Radioactive Iodine Therapy is a safe and effective treatment for hyperthyroidism and thyroid cancer. Hypothyroidism is a common side effect associated with RAI.

Other possible long term side effects include:

  • Inflammation of the salivary glands
  • Fatigue
  • Dry or watery eyes
  • Lower levels of blood cells
  • Breathing problems
  • Infertility and/or impotency
  • Secondary cancers

8. Are there any short-term side-effects?

Short-term side effects of RAI treatment may include:

  •         Neck tenderness and swelling.
  •         Nausea and vomiting.
  •         Swelling and tenderness of the salivary glands.
  •         Dry mouth.
  •         Change of taste in the mouth

9. Who is this therapy not indicated for?

Radioactive iodine therapy cannot be used to treat anaplastic (undifferentiated) and medullary thyroid carcinomas because these types of cancer do not take up iodine. Radioactive iodine therapy is also not used if you are pregnant, planning to get pregnant, or are breastfeeding.

10. Insurance coverage

If your doctor has approved your radioactive iodine therapy care plan, contact your insurance provider to find out if preauthorization is required for RAI therapy to provide insurance coverage. Preauthorization is the determination made by your health insurance company that this procedure is necessary.

11. How to pick the right doctor and centre for the therapy?

Picking the right treatment facility for your iodine therapy is crucial. Here are a few things you should look out for –

Hospital facilities nearby: It is advisable to have your treatment in a centre which is either within a hospital or has a hospital nearby. This is important to make sure you have quick access to emergency medical care if needed. 

Accreditations of the facility: You must also make sure the facility is accredited by AERB. 

Proper nuclear medicine specialists: You should also find out about your doctor or group of doctors, how well-versed they are with this therapy, how often and for how long they’ve been administering Iodine therapy. 

Accreditations of the facility: You must also make sure the facility is accredited by the respective bodies like the ATA and AERBP. 

Trained technicians: The facility you visit should also have qualified, experienced and trained technicians who will be capable of handling any situation well. You should also find out for how long these technicians have been administering the therapy.performed the duties they’ve been given. 

Insurance acceptance: The facility should also have a  TPA desk and most likely be approved by your insurance agency so the cost of the therapy is appropriately covered. 

COVID safety: With COVID looming over us, it’s never a bad idea to see and understand what safety measures the facility follows to prevent the spread of infection.

Gauge your doctor: Your consulting doctor should be open to answering questions, be well-versed with the process, possible emergencies. He/she should also be willing to guide you through the process and tell you clearly about any side effects or discomfort you might face. 

Amenities: The facility you choose should also have specialized infrastructures such as isolation and drainage system.

Location: If you are travelling to India for treatment, you should make sure that the facility you choose is in the centre of the city, with access to amenities.

Now that you’ve understood the basics of Radio-iodine therapy, let’s get down to the specifics of therapy for thyroid cancer and hyperthyroidism:

A. Common questions about Iodine therapies