will my cat gain weight after radioactive iodine treatment
Many owners of cats with hyperthyroidism are hesitant to have radiation therapy or surgery because of their cat's advanced age. In a cat treated with radioactive iodine, the drool will contain radioactive materials. When the dose of radiation to the thyroid is very low, like might occur by accidental ingestion of litter box contents, then mutations leading to cancer can ensue. Lack of appetite. 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. AAFCO Doesnt Approve Pet Foods, A broken heart: Risk of heart disease in boutique or grain-free diets and exotic ingredients, Its Not Just Grain-Free: An Update on Diet-Associated Dilated Cardiomyopathy. The most common clinical signs of hyperthyroidism are weight loss, increased appetite, and increased thirst and urination. 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. Thyroid scintigraphy may also be recommended to confirm a diagnosis and determine the size of the organ before surgery or radioactive iodine. Most cats with uncomplicated hyperthyroidism will live several years following treatment of hyperthyroidism, unless they develop another disease. The food isnotmedicated. What is happening in this procedure is that a portion of the radioactive iodine is being taken up by the cat's thyroid to treat its condition (hyperthyroidism, I assume?). Oftentimes it takes decades for cancer to be detected following radiation exposure. The study followed people for 26 years after two or more treatments. J Am Vet Med Assoc, 2006. Cats treated with radioactive iodine for their hyperthyroidism have several risks unrelated to the radioiodine therapy itself. Nera just had her 3 month checkup and her T4 level is down to 2.3! When an injection of radioactive iodine is given, it destroys the abnormal thyroid tissue without endangering other organs. We love them, too! They will then need to take a thyroid supplement. When x-rays, or any ionizing radiation, pass through the body they cause electrons to be ejected from atoms, leaving behind positive ions. 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. So, we must use distance and reduction of time near the source when dealing with patients and pets treated with 131I. JavaScript is disabled. Because of strict treatment guidelines, most facilities will not allow visitors during this quarantine period. Cat Articles | Further, the litter will be radioactive as most of the radioactive iodine will be excreted via this route. 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). Radioactive iodine therapy. Hence for a transient period following radioiodine therapy, the patient's urine contains excreted radioiodine which will emit beta particles as it continues to decay. Depending on the dose, radioactive iodine can kill a portion, or all, of your thyroid. Now let's deal with the issue of radioactive iodine released by the cat, which I believe is actually the bigger concern. Diagnosis of feline hyperthyroidism is generally straightforward. It is also common for hyperthyroid cats to exhibit increased vocalizing, particularly at night. Several complications of hyperthyroidism can be significant, includinghypertension(high blood pressure) and a heart disease called thyrotoxic cardiomyopathy. A prescription diet is available that lowers thyroid hormone, but for it to work your cat can't ever eat any other food. This usually leads to permanent destruction of the thyroid, which will cure hyperthyroidism. First we need to put this exposure level into some context: How do x-rays increase your risk for cancer? These medications do not provide a cure for the disease, but they do allow either short-term or long-term control of hyperthyroidism. During treatment, radioactive iodine is administered as an injection and is quickly absorbed into the bloodstream. For this reason, some cats with hyperthyroidism may require additional treatment to control secondary heart disease. Although many cats diagnosed with hyperthyroid disease already have kidney disease, untreated hyperthyroidism can also cause kidney disease due to the damaging effects of hypertension on the kidneys. You would actually have to ingest the cats waste for it to be harmful to you. Get exceptional Radioactive Iodine Therapy for Feline Hyperthyroidism services from highly experienced & loving pet care professionals in Downers Grove, IL. Symptoms include weight loss, muscle wasting, increased appetite, increased thirst and urination, vomiting, unkempt appearance, and sometimes hyperactivity. It requires two round-trips for you. Nuclear Medicine Patient Issues Questions Concerning Domestic Animals. Remember that theNRC regulationsrequire that release criteria and discharge instructions provided to owners of hyperthyroid cats prevent exposures of more than 1 mSv. Always check with your veterinarian before changing your pets diet, medication, or physical activity routines. So in this case the targeted radiation exposure is actually increasing survival for these patients. 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. The risks associated with low level ingestion of radioactive iodine relate to an increased risk of developing thyroid cancer. Only about 5% of hyperthyroid cats are younger than 10. Let's tackle the external exposure first as it is the simplest concept. Some places realize that the stress of being away from home for so long is not good for older cats. Risks unrelated to radioiodine therapy: Cats treated with radioactive iodine for their hyperthyroidism have several risks unrelated to the radioiodine therapy itself. Since hyperthyroidism can predispose a cat to other conditions, it is important to evaluate general health, with particular focus on the heart and kidneys. Hyperthyroidism is too much thyroid hormone that causes weight loss so kitty should gain some weight back to a normal amount after treatment. This is due to increased stimulation in the nervous system which is a common occurrence in cats with feline hyperthyroidism. 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. What they are trying to prevent is the intake (ingestion, etc.) Feeding an iodine-limited diet (Hills Prescription Diet y/d) can resolve clinical signs and lower thyroid hormone concentration. Researchers estimated a 12% increased risk for death from breast cancer and a 5% increased risk for death from . Weight gain after RAI is typical. Prior to the onset of symptoms he was eating a high quality dry cat food but when he started losing weight and begging for food we were told we could . If you know that your cat has hyperthyroidism, you probably have already seen your vet in order to have this disease properly treated. Your doctor will order a test called a radioactive iodine uptake and scan to determine the dose you will need. RAI is a form of radioactive nuclear medication that permanently destroys thyroid tissue. Radioactive iodine therapy is becoming the treatment of choice for felines with hyperthyroidism. The required dose of methimazole can change over time, so monitoring thyroid levels in treated animals is recommended every 3-6 months once their condition is stable. In some cases, a decrease in blood platelets (thrombocytopenia) may also occur. Answer posted on 30 March 2019. However, caution should be taken in disposal of products that may contain trace amounts of this radioactive substance. For a better experience, please enable JavaScript in your browser before proceeding. There are two types of radiation exposure that your vet is trying to minimizeexternal exposure from the radioactive material within the cat's body, and the radioactive materials in the cat's urine and other bodily fluids released by the cat that you may come into contact with and may end up being ingested or absorbed by you accidentally. 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. Hair loss. Part 20, Standards for protection against radiation Anti-thyroid drugs act by reducing the production and release of thyroid hormone from the thyroid gland. One to two weeks after surgery, another TT4 level is measured. Risks from hyperthyroidism. Why is the average risk of developing cancer so high? Because each cat is different, your veterinarian will advise you on the best treatment for your cat. The effectiveness of this transdermal gel is acceptable in most cases. Subscribe to always know when we add new material! Do not allow your cat to sleep against your body. Did You Know? Treatment The current Nuclear Regulatory Commission radiation dose limits for individual members of the public are listed below. The thyroid cells are damaged or destroyed, but that's the whole idea other cells are left untouched. Radioactive iodine. I'll be honest, the last thing I (or my vet) worried about with Sara was gaining weight. In an effort to put some weight back on him we are still feeding him turkey and gravy baby food in the morning to supplement the dry food. Also, you might get some good ideas about what to feed him on Dr. Lisa Pierson's web site. The total effective dose equivalent to individual members of the public from the licensed operation does not exceed 1 mSv in a year, exclusive of the dose contributions from background radiation, from any administration the individual has received, from exposure to individuals administered radioactive material. Dietary restriction of iodine is, however, somewhat controversial because of concerns about the effects of long-term iodine restriction on overall health and the possibility that such a diet may actually backfire and worsen hyperthyroidism. Although this procedure is usually very effective, it is more expensive and requires the cat being . Limit close contact (closer than 1 foot) to one hour per day. What this means is that occasionally we invest clients economic and perhaps more importantly, emotional resources in treating and resolving hyperthyroidism is cats with other, currently unknown diseases. In addition to reporting for a major newspaper chain, she has been published in "Horse News," "Suburban Classic," "Hoof Beats," "Equine Journal" and other publications. Affiliate of Mars Inc. 2023 | Copyright VCA Animal Hospitals all rights reserved. Risks unrelated to radioiodine therapy: 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 cell repairs itself perfectly (most common result). To scientifically prove a connection would require nearly one million patients followed closely over decades to detect the small increased risk with any confidence. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. A special diet for cats with hyperthyroidism. Antithyroid medications are also available in a gel that can be applied to the skin. Risks from other illness. Radioactive iodine therapy. Hypocalcemia can be life-threatening and may require either short-term or long-term medication postoperatively should it occur. NRC Regulations When available, radioactive iodine therapy is the treatment of choice for cats with hyperthyroidism. With your cat's diseased thyroid, after methimazole treatment failed, large doses of iodine might have proven effective. Surgical removal of the gland under general anesthetic was another option. She gained and ate a lot and we were more than happy. . Often, treating hyperthyroidism will unmask hidden kidney failure that will require additional care and is best detected early in the course of the disease. You should use the following methods for disposing of your cat's waste that may contain trace amounts of radiation. He rejected the Fancy Feast stuff and gobbled the baby food along with eating a little variety of the many dry foods we tried in an effort to find one that he really liked. Discuss these issues with your veterinarian when considering dietary iodine restriction as a treatment for hyperthyroidism in cats. The AVMI radioactive materials license utilizes release criteria and precautionary instructions specifically based on the evaluation of the relative exposure levels to clients following radioiodine therapy for hyperthyroid cats treated with I-131. ), family history (genetics) or radiation exposure. Dietary Therapy This test can also help the doctor determine the cause of your hyperthyroidism and get other information about your thyroid tissue. Recurrence of the disease is a possibility in some cats. Many organs are affected by hyperthyroidism, especially the heart. Luckily these risks will diminish in time following successful radioiodine therapy and a return to a persistently normal thyroid level. 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. Radioactive iodine may also affect a woman's ovaries, and some women may have irregular periods for up to a year after treatment. About 25% of cats with hyperthyroidism become hypertensive. Objective: To investigate the long-term effects of continuous methimazole (MMI) therapy. 122(6): p. 2444-61. This lowers the amount of radiation exposure to your bladder. Ideally, the total GFR should be above 2.25 mL/min/kg. What may work for one cat may not work for another. The radioactive isotope, Iodine-131 ( 131 I), is administered as a one-off injection. By 14 days after treatment, the radioactivity will have decayed to a very low level. Ultrasound of the heart (called echocardiography) may be recommended based on your cat's condition, especially if there is any concern about cardiomyopathy. Does radioactive iodine treatment cause weight gain? Generally, about 5 to 10 pounds of excess weight can likely be attributed to the lack of thyroid hormones that occurs in people diagnosed with hypothyroidism. The radioactive iodine is administered as a single injection . 8. Conveniently, the main use of iodine in the body is the production of thyroid hormone, so a deficient diet shouldnt cause any other health issues in a hyperthyroid cat. It is important to drink fluids after your treatment and for the next 2 days. Affected cats produce too much thyroid hormone. 7. Prognosis This disease is common in older cats. Surgery will be performed if your cat successfully undergoes the initial treatment without complication. Try mixing baby food chicken or turkey in with some Fancy Feast. If your cat does not have elevated T4 levels but your veterinarian still suspects your cat has hyperthyroidism, additional tests may be recommended. Wet food is much better for him anyhow, so this is a good time to get him settled on it. The radioactivity carries no significant risk for the cat, but precautionary protective measures are required for people who come into close contact with the cat. Your cat may be hospitalized for one to two nights following surgery and should begin to eat and behave normally after returning home. Fewer than 2% of hyperthyroid cases in cats involve malignant thyroid gland tumors. Title 10, Code of Federal Regulations It is used less commonly in younger children. This is very important meaning that cats rarely develop an underactive thyroid gland (hypothyroidism) after radioiodine therapy. In a cat treated with radioactive iodine, the drool will contain radioactive materials.