The risk to these cats is the simple fact that many cats in the age range when cats develop hyperthyroidism (8+ years) also develop other diseases. Regardless of the medication, blood tests should be conducted periodically during treatment to evaluate whether the therapy is effective and to monitor kidney function and for potential side effects. One study looked at patients with Graves' disease who were treated with RAI over five years. Hyperthyroid cats are also at risk for complications related to the hypertension that frequently accompanies hyperthyroidism. What Are The Side Effects Of Radioactive Iodine Treatment In Cats? Until then, the radiation safety guidelines of Michigan and the NCR are followed. Radioactive iodine is a treatment for an overactive thyroid gland. Number of cases per 100,000 persons exposed to a single dose of 0.1 Gy. Although the cause of feline hyperthyroidism is not known, possible contributing factors include deficiencies or excesses of certain compounds in the diet and chronic exposure to thyroid-disrupting chemicals in food or the environment. The "radiation badge" worn by x-ray techs for example is good for measuring external exposure to radiation but does nothing to measure intakes of radioactive materials which is the primary concern in the case of a cat treated with radioactive 131I. Usually this means that the cat will need to be hospitalized for between three and five days after treatment. Thyrotoxic cardiomyopathy may develop because the heart enlarges and thickens to meet the increased metabolic demands.
This problem resolved rapidly after treatment. Hyperthyroidism is a common condition in older cats. Methimazole blocks excess thyroid hormone production rather than destroying the abnormal thyroid tissue, so the medication must be given for the rest of the cat's life. However, once the underlying hyperthyroidism has been controlled, the cardiac changes will often improve or may even resolve completely. In a study of 524 hyperthyroid cats treated with I-131, only 11/524 (2.1%) developed The following question was answered by an expert in the appropriate field: What testing equipment and protective clothing do you recommend for a nontechnical person who will be giving home care to an 18-year-old blind cat after he has spent four days recovering in the animal hospital from 131I treatment? It is given one to three times daily and must be continued for the remainder of the pet's life. . Because of the short distances they travel they never exit the patient and as a result no one other than the patient is at risk from exposure to the beta particles unless they internalized the radioiodine excreted by the patient. Whats the difference between type 1 and 2 diabetes NHS. Does radioactive iodine treatment cause weight gain? They do not take into consideration individual risk factors including lifestyle (smoking, diet, exercise, etc. Their hyperthyroidism won't come back, and they don't need ongoing medication. Actually it is quite safe, because the radioactive iodine is absorbed only by thyroid cells; no other cells in the body are exposed to the radiation. No ill effects have been noted in the children born to parents who received radioactive iodine in the past. Methimazole is also given before surgery to determine if the cat has a secondary medical condition, such as kidney or liver disease masked by hyperthyroidism. Now that I know my cat has hyperthyroidism, what do I do? Despite the extensive blood and urine tests, chest x-rays and physical exams that we require before radioiodine therapy, some of these conditions remain undiagnosed at the time of radioiodine therapy. The beta particles, which are much more potent forms of radiation, travel an average distance of less than 1 mm. Finally, thyroid hormone has a role in kidney function and blood flow that may result in either directly damaging the kidney or obscuring underlying kidney disease that your cat may already have. Radioactive iodine may also affect a woman's ovaries, and some women may have irregular periods for up to a year after treatment. Radioactive-iodine therapy is becoming increasingly popular when dealing with hyperthyroidism in cats. 1 INTRODUCTION. Most of the extra radioactive iodine is eliminated in your urine. If hypertension is diagnosed along with hyperthyroidism, drugs may be needed to control the blood pressure and reduce the risk of damaging other organs. Risks unrelated to radioiodine therapy: Radioactive iodine targets the thyroid tissue - as this is the only tissue in the body that uses significant quantities of iodine. Laura Porter / Verywell When it comes to survival, the studies that have been done show that cats cured of their thyroid disease by radioactive iodine live much longer (up to twice as long) when compared to hyperthyroid cats treated by methimazole. If your cat does not have elevated T4 levels but your veterinarian still suspects your cat has hyperthyroidism, additional tests may be recommended. Companion Animal Hospital in Ithaca, NY for cats, dogs, exotics, and wildlife, Equine and Nemo Farm Animal Hospitals in Ithaca, NY for horses and farm animals, Cornell Ruffian Equine Specialists, on Long Island for every horse, Ambulatory and Production Medicine for service on farms within 30 miles of Ithaca, NY, Animal Health Diagnostic Center New York State Veterinary Diagnostic Laboratory, Cornell University College of Veterinary Medicine Ithaca, New York 14853-6401. Dr. Freeman has received research or residency funding from, given sponsored lectures for, or provided professional services for Aratana Therapeutics, Elanco, Guiding Stars Licencing Co LLC, Hills Pet Nutrition, Nestl Purina PetCare, P&G Petcare (now Mars), and Royal Canin. If the nearest facility is far away, there's the stress or travel for both you and Fluffy, as well as possible hotel and other travel expenses. They will then need to take a thyroid supplement. Cats may also continue to show signs of hyperthyroidism, including vomiting and diarrhea, for 3-4 weeks after the radioiodine therapy as the disease continues to resolve. Currently, there's only one FDA approved medication to treat feline hyperthyroidism called methimazole. The brand name of methimazole is called Felimazole. The dosage may vary but typically a cat is given this oral medication twice a day, every 12 hours. . These include weight loss, increased activity, and kitten like behaviour. Radioactive iodine therapy is curative within three months of therapy in approximately 95 percent of all hyperthyroid cases. (For example, for human patients we provide instructions such as "sleep in separate beds" and "stay at least 1 meter away from others as much as possible.") However, an overactive thyroid is quite common. This is due to increased stimulation in the nervous system which is a common occurrence in cats with feline hyperthyroidism. This lowers the amount of radiation exposure to your bladder. It is important to drink fluids after your treatment and for the next 2 days. J Am Vet Med Assoc, 2006. Research into this potential treatment option is ongoing. Determination of Release Criteria for I-131 Therapy Cats in Conference Proceedings American College of Veterinary Radiology. It has the advantage of being curative in most cases with no ongoing treatment. When choosing the best therapy for an individual cat, many factors must be considered. The ALARA recommendation follows the classic "less is more" argument and hence adherence to this philosophy suggests that exposures to ionizing radiation should be minimized whenever possible. Only the bare necessitiesfood and water and quick litter cleanupsare provided by veterinary technicians during your cat's hospital stay. Many times the only symptoms these other conditions cause are weight loss. Radioactive iodine is an effective and safe treatment option for children and teenagers with an overactive thyroid gland, but will usually be given as a second-line treatment after a reasonably long course of antithyroid medication. If you suspect your cat might be experiencing some of these symptoms, the next step is visiting your veterinarian for a blood test to check your cats thyroid hormone levels. In most cases, only enough radioiodine is given to destroy that part of the gland that is functioning .
This surgery requires general anesthesia, however, and there might be added risks if older cats have heart, kidney, or other problems that could cause complications. All bodily fluids in the cat will have trace amounts of radioactive material within them, but it will be most prevalent within the urine. If you know that your cat has hyperthyroidism, you probably have already seen your vet in order to have this disease properly treated. Prescription nutrition. There are no studies that directly link cancer to the low dose radiation used in current medical imaging. "The most common clinical sign of hyperthyroidism is weight loss due to the increased rate of metabolism despite an increased appetite.". The radioactive iodine damages these cells and causes your thyroid to shrink and thyroid hormone levels to go down over a few weeks. The average age of cats with hyperthyroidism is approximately 12 years and about 5% of hyperthyroid cats are younger than 10 years of age. Radioactive iodine therapy. Surgical patients may become hyperthyroid again if abnormal cells are missed during surgery or if new abnormal cells develop. The dose of radiation used during radioactive iodine treatment is very low, but there are some precautions you'll need to take after treatment: avoid prolonged close contact with children and pregnant women for a few days or weeks women should avoid getting pregnant for at least 6 months men should not father a child for at least 4 months The three ways that we control exposures to external sources of radiation are time, distance, and shielding. 2 The goal of RAI treatment is to restore euthyroidism while avoiding the development of hypothyroidism. What happens after radioactive iodine treatment for cats? Clinical Signs An anti-thyroid medication, like methimazole. If these tests are not diagnostic, athyroid scan (thyroid scintigraphy)can be performed at a veterinary referral center, or the TT4 can be measured again in a few weeks. We found out about the radioactive iodine treatment and after lots.of research decided this was the way to go. (a) Each licensee shall conduct operations so that -. The advantage of surgery is that it is likely to produce a long-term or permanent cure in most cats, and therefore eliminates the need for long-term medication. There are four treatment options for feline hyperthyroidism: medication, radioactive iodine therapy, surgery, and dietary therapy. What is not taken up by the thyroid will be present in the cat's bodily fluids and will primarily be voided in the cat's urine (in those first four days at the vet hospital). Log in 24/7 to access your pets health care information. The remainder is gone in about the next two months or so. Over ten years of clinical nutrition research revealed that by controlling dietary levels of iodine, the hyperthyroid cat's body would resume normal thyroid hormone production. Additionally, diet may play a significant role in managing the disease, whether as a sole treatment or as an adjunct tool to address changes in your cats body related to hyperthyroidism. The food isnotmedicated. Cats also sweat through their paws and the sweat will have trace amounts of radioactive iodine.