will my cat gain weight after radioactive iodine treatment
To date the studies following hyperthyroid cats treated with radioiodine have not shown any increased incidence of cancer (thyroid or other types) associated with radioiodine therapy. As for your dose, my primary concernespecially if you were allowing the cat to have direct, prolonged contact within the first week of releasewould be the potentially contaminated materials that could result in your intake of radioactive 131I. There are several hypothesized causes of hyperthyroidism. 35(3): p. 204-209. That was part of the problem we had before treatment. 7. The effectiveness of this transdermal gel is acceptable in most cases. However, because your cat will be radioactive for several days after receiving the shot, precautions must be taken during and after the treatment. How to choose the right food for your cat. Cats treated with radioactive iodine for their hyperthyroidism have several risks unrelated to the radioiodine therapy itself. Their hyperthyroidism won't come back, and they don't need ongoing medication. Why is the average risk of developing cancer so high? You may also be advised to suck on sour candy after treatment to help the radioactive iodine come out in your saliva. Because the radioactive iodine used (known as iodine 131) may expose those around you to the effects of radiation (and theoretically negatively affect their thyroid glands), you will be given guidelines on how to prevent such exposure. This helps us offset the costs of running this site, so thank you for your support! When an injection of radioactive iodine is given, it destroys the abnormal thyroid tissue without endangering other organs. 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. The normal thyroid cells will therefore not take up any radioactive iodine. Category: Nuclear Medicine Patient Issues Questions Concerning Domestic Animals. Medication typically. Until then, the radiation safety guidelines of Michigan and the NCR are followed. Prognosis Also, you might get some good ideas about what to feed him on Dr. Lisa Pierson's web site. All middle-aged and senior cats should receive a complete physical examination by a veterinarian every six months. In a cat treated with radioactive iodine, the drool will contain radioactive materials. The risks associated with low level ingestion of radioactive iodine relate to an increased risk of developing thyroid cancer. When choosing the best therapy for an individual cat, many factors must be considered. To answer these questions we have to separate the risks associated with internalizing (i.e., ingesting) radioactive iodine from the risks of being around a patient that has been treated with radioactive iodine. After treatment, the normal thyroid tissue will regain full function within 1-3 months. However, caution should be taken in disposal of products that may contain trace amounts of this radioactive substance. Cats are homed in our spacious, purpose-built radioactive iodine unit and cared for by our dedicated team of radioiodine nurses. "The most common clinical sign of hyperthyroidism is weight loss due to the increased rate of metabolism despite an increased appetite.". People may take RAI . This treatment involves administering an injection of iodine with a radioactive substance attached. Cornell University College of Veterinary Medicine, Cornell Ruffian Equine Specialists, on Long Island, Cornell Veterinary Experts Address Feline Nutrition. As with surgery, you may need to take thyroid hormone . What Are The Side Effects Of Radioactive Iodine Treatment In Cats? Now that I know my cat has hyperthyroidism, what do I do? A seven hour airplane trip exposes passengers to 0.02 mSv of radiation, which is a fraction of the exposure of a standard Chest x-ray (0.1 mSv). Part 20, Standards for protection against radiation I'll be honest, the last thing I (or my vet) worried about with Sara was gaining weight. Chance of significant, unhealthy weight gain is increased. Annual blood and urine tests are important in all cats seven years and older to detect hyperthyroidism before potentially irreversible damage occurs. 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 American Thyroid Association notes that weight gain develops over a long time and may have many causes other than the underactive thyroid. Scaly skin. The slow onset of signs means that cat owners will often miss these changes until the late stages of disease. Lack of appetite. Risks unrelated to radioiodine therapy: 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. The advantages of radioactive iodine therapy are that the procedure most often cures hyperthyroidism, has no serious side effects, and does not require anesthesia. Did You Know? 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. Keeping your pets food temperature just right. The treatment of choice for hyperthyroid cats is radioactive iodine therapy, which is a cure. Radioactive iodine is a treatment for an overactive thyroid gland. Rarely, a permanent reduction in thyroid-hormone levels called hypothyroidism occurs after radioactive iodine treatment. Many organs are affected by hyperthyroidism, especially the heart. If we restrict iodine, production of thyroxine decreases. The first step is determining the blood level of one of the thyroid hormones calledtotal thyroxine (TT4). Your veterinarian has recommended I131 for your cat. Some rare cases of hyperthyroid disease are caused by malignant tumors known as thyroid adenocarcinomas. Hyperthyroid cats are also at risk for complications related to the hypertension that frequently accompanies hyperthyroidism. It is also common for some cats to hide under the bed for a day or so after returning home as they de-stress following their out of home experience. But those instruments are quite expensive and are not readily available in stores. Do not allow your cat to sleep against your body. 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. Usually, the TT4 level is so high that there is no question about the diagnosis (see the handout "Thyroid Hormone Testing in Cats"). Although it has a slightly higher iodine content than the previous option, Tiki Cat Hanalei Luau Wild Salmon is the best value for money. Only about 5% of hyperthyroid cats are younger than 10. An anti-thyroid medication, like methimazole. This can best be done by monitoring your cats body condition, muscle condition, and weight. Why isn't there a study directly linking medical imaging and cancer? Your doctor will order a test called a radioactive iodine uptake and scan to determine the dose you will need. Recurrence of the disease is a possibility in some cats. 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. Affected cats produce too much thyroid hormone. The iodine, which is required for the production of both T3 and T4, is taken up by the thyroid gland and the emitted radiation destroys the abnormal thyroid tissue without damaging the surrounding tissues or the parathyroid glands. He also can't sleep with you during that time, and the facility will inform you about special arrangements you'll have to make for disposing of his litter. More specific information on what to expect when your cat is treated with radioactive-iodine therapy at Cornell can be found here. When this occurs, a second test, usually afree T4 by equilibrium dialysis (FT4 by ED)or aT3 suppression test,is performed. Hyperthyroid cats suffer overactive thyroid glands, circulating too much thyroid hormone through their system and affecting nearly every organ. I-131 is normally a health concern after the . While in radiology we use radiation shielding garments (lead aprons) to reduce gamma and x-ray exposure, the energy of the 131I gamma is four to five times higher and those garments are ineffective as a shield. Prescription nutrition. 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. The three ways that we control exposures to external sources of radiation are time, distance, and shielding. This is why one of the first signs of thyroid disease may be a change in weight weight gain if the thyroid is underactive and weight loss if the thyroid is overactive. The food isnotmedicated. Slater M.R., Komkov A., Robinson L.E., et al., Long-Term Follow-up of Hyperthyroid Cats Treated with Iodine-131. Toxicology and Applied Pharmacology, 2004. It has to do with how important your thyroid is in regulating your metabolism and your weight. Within one year after discontinuation of MMI, hyperthyroidism recurred in 104 patients. I'm sure if he is still underweight, his body will be telling him to eat, eat, eat. Amazingly despite over 35 years of veterinary experience treating hyperthyroid cats with radioiodine there are virtually no reported side effects. Radioactive iodine (RAI) is a treatment method for hyperthyroidism and thyroid cancer. However, because your cat will be radioactive for several days after receiving the shot, precautions must be taken during and after the treatment. Consider Hyperthyroid Treatment . Whats the difference between type 1 and 2 diabetes NHS. J Am Vet Med Assoc, 2006. There are fundamental differences between a continuous dose over a year (background radiation) and a dose that occurs over a few seconds like in CT, but these are helpful comparisons. The School of Veterinary Medicine's Ryan Hospital, however, is one of the few veterinary centers in the region to offer a treatment that can cure the disease: a single shot of radioactive iodine, I-131. Radioactive iodine therapy is curative within three months of therapy in approximately 95 percent of all hyperthyroid cases. . You may gain weight after you undergo radioactive iodine treatment. The thyroid cells are damaged or destroyed, but that's the whole idea other cells are left untouched. When an injection of radioactive iodine is given, it destroys the abnormal thyroid tissue without endangering other organs. . It is actually the best approach to take to minimize exposures to you and your family while allowing the cat to have post-treatment recovery time at home and not in a veterinary hospital. Radioactive iodine therapy. The veterinarian's recommendations are to isolate my cat for at least two weeks. An important take-away message about your newly-diagnosed hyperthyroid cat is that there is a wide range of treatment options, so you can likely find something that works for your family. As youre on this website right now, we can assume that you love pets and likely have a special dog or cat (or many) in your life. Set up your myVCA account today. The radioactive iodine damages these cells and causes your thyroid to shrink and thyroid hormone levels to go down over a few weeks. Medication Studies have shown that cats treated with I-131 live longer than those treated with pills, added Mosenco, citing a study where I-131-treated cats lived an average of four to five years following treatment, versus an average of only two years for cats on medication.Dec 19, 2016. The estimates of risk currently used are extrapolated from patients that have received much higher doses (e.g., atomic bomb survivors) using the linear, no-threshold model of radiation exposure risk. Since hyperthyroidism can predispose a cat to other conditions, it is important to evaluate general health, with particular focus on the heart and kidneys. The only method to estimate that dose is to measure the radioiodine within your own thyroid and the types of equipment to measure that uptake are very expensive and difficult to interpret. As in the case of heart disease, after the hyperthyroidism has been successfully treated, high blood pressure will often resolve, and permanent treatment for it may not be required. This means that our radioactive materials license requires our practice ensure that our clients receive less than 1 mSv of radiation exposure as the result of our treatment of their hyperthyroid cat with radioiodine. Dry, dull coat. Objective: To investigate the long-term effects of continuous methimazole (MMI) therapy. Surgery or radioactive iodine therapy to regulate overactive hormone production can sometimes leave cats with the opposite problem: their levels of thyroid hormone are now too low. Hypothyroidism, is a condition resulting from a deficiency of thyroid hormone. I have a cat also and I know when she is happy and purring while sitting on my lap getting strokes, she drools. Subscribe to always know when we add new material! Home & Forums | Vet Rad & Ultrasound, 1994. Radioactive Iodine Therapy Blog written by Dr. Daisy Spears in conjunction with Dr. Linder. Your cat will not experience nausea, hair loss, lethargy, or decreased appetite as a result of the procedure. Lifelong treatment, usually involving twice-daily oral dosage, will be required, and for some owners and cats, this dosage schedule may be difficult to maintain. A veterinarian who suspects a cat has a thyroid problem will conduct a physical examination and palpate the cats neck area to check for an enlarged thyroid gland (see Figure 2). Special attention should be given to the thyroid glands to look for evidence of enlargement and the clinical signs of hyperthyroidism. Risks from hyperthyroidism. Interestingly, when higher doses are given, like those received by the patient treated for hyperthyroidism or thyroid cancer, then the injury to the cells is terminal and hence the cells do not survive to go on to become malignant. These tests are needed to evaluate your cats overall health and predict the likelihood of complications with the chosen treatment protocol. Cats can receive a second treatment, if necessary. Radioactive iodine therapy. Discuss these issues with your veterinarian when considering dietary iodine restriction as a treatment for hyperthyroidism in cats. About 25% of cats with hyperthyroidism become hypertensive. The current Nuclear Regulatory Commission radiation dose limits for individual members of the public are listed below. Survival Times for Cats with Hyperthyroidism Treated with Iodine 131, Methimazole, or Both, http://www.nrc.gov/reading-rm/doc-collections/cfr/part020/, Determination of Release Criteria for I-131 Therapy Cats, Risk of Ionizing Radiation Exposure to Children: A Subject Review, Hormesis: From Marginalization to Mainstream: A Case for Hormesis as the Default Dose-Response Model in Risk Assessment. This isnotan iodine-free diet but a diet with a controlled iodine content of 0.2ppma minimal amount. Elevated thyroid hormones stimulate an increased heart rate and a stronger contraction of the heart muscle, and can cause thickening of the left ventricle of the heart over time. Copyright 2023 Leaf Group Ltd. / Leaf Group Media, All Rights Reserved. This may take 8 to 12 weeks or longer. Note that the reference above excluding licensee's from considering "exposure to individuals administered radioactive material" in their compliance with the NRC regulartions does not apply to animals. The typical cat with hyperthyroidism is middle-aged or older; the average age of affected cats is approximately 12 years. How does airline travel expose me to radiation? What Treats Can I Give my Dog with CalciumOxalateStones? Iodine-131, Hyperthyroidism, and Radioactive Iodine Therapy Iodine-131 (I-131) is a radioisotope of iodine with a physical half-life of 8.02 days; its primary decay emissions include a 606 keV - particle with 89.6% abundance and a 364 keV -ray with 81.5% abundance (Knolls Atomic Power Lab 2010). You must log in or register to reply here. 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? If possible, I would like to wear protective clothing so we can return to our familiar habit of living/sleeping in 24-hour close physical contact to minimize his stress and promote his recovery. For this prescription diet to work, it must be the only food fed, which means no cheating with treats. Should we just cut him off "cold turkey" (pun intended) and hope he finds fulfillment and eventual weight gain with his old diet of dry food? 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. . In some cases, the cat will develop a heart murmur associated with cardiomyopathy. Radioactive iodine. She has spoken at national and international conferences and a Capitol Hillbriefing, and is an expert in pet obesity, nutrition communication, and in the human-animal bond. Hypertension, or high blood pressure, is another potential complication of hyperthyroidism, and can cause additional damage to several organs, including the eyes, kidneys, heart, and brain. By Follow up blood work is essential to ensure kitty does not become hypothyroid which is too little thyroid. Clients owning hyperthyroid cats undergoing radioiodine therapy are always considered members of the general public. It is given one to three times daily and must be continued for the remainder of the pet's life. However, there are a number of reasons for the precautions that your veterinarian has provided you that I will discuss below. You would actually have to ingest the cats waste for it to be harmful to you. Researchers estimated a 12% increased risk for death from breast cancer and a 5% increased risk for death from . Risk of Ionizing Radiation Exposure to Children: A Subject Review. The Disadvantages of Radioiodine Therapy Treatment for Cats, American Veterinary Medical Imaging: Feline Hyperthyroidism, Washington State University College of Veterinary Medicine: Radioactive Iodine Treatment of Hyperthyroid Cats, Washington State University College of Veterinary Medicine: Hyperthyroidism in the Cat, Cornell University College of Veterinary Medicine: Hyperthyroidism in Cats. Unfortunately, 131I has a rather high-energy gamma emission that is difficult to shield. These statistics are averages and do not predict what is going to happen to you. These include an iodine-restricted diet, medications, and radioactive iodine therapy. Surgery. Before deciding the form of treatment, several tests are performed, including additional blood tests, a urinalysis, chest radiographs (X-rays), an ECG, and blood pressure measurements. You may feel a lump on your cat's throat under his jaw. (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.") There are virtually no side effects, and there is no pain associated with 131I treatment. Dr. Deborah Linder, a board-certified veterinary nutritionist, is the head of the Tufts Obesity Clinic for Animals and has had articles appear in Eating Well, the Boston Globe, AARP, SHAPE, and XM Sirius Radio Doctor Channel. In cases where radioactive iodine therapy is not successful, the treatment can be repeated. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. Committee on Environmental Health. What are other nutritional concerns for my hyperthyroid cat? Does radioactive iodine treatment cause weight gain? Cats receive a single dose of radioactive iodine by either subcutaneous injection or by a capsule given by mouth. In some cats, anorexia develops as the disease progresses. A special diet for cats with hyperthyroidism. There are currently no known preventive measures for hyperthyroidism, but early diagnosis decreases the secondary problems and improves the prognosis. Want to read more information on feeding your pet? The risks of ingesting radioactive iodine and the risks of being around a patient that has been treated with radioactive iodine are very different.
