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  1. 1. Graedons’ Guide to Visit our Web site: Thyroid Hormones T Symptoms of Low Thyroid T he thyroid gland has surprising power for such an unobtrusive or- gan. It controls how fast every cell body such as the legs, underarms and pubic region in addition to the scalp. The doctor will also check for a slow Activity in the body uses energy. It also Achilles reflex, look for a swollen area affects cells’ response to growth hormone around the eyes, and ask about a Apathy and other compounds, including estrogen woman’s menstrual cycle. Heavy bleed- Fatigue and calcium. Because of its widespread ing may be associated with inadequate Dry skin impact, though, symptoms of thyroid prob- thyroid hormone, and women without Weakness lems may be vague and general, making enough thyroid may have trouble get- Constipation diagnosis difficult. ting pregnant. Depression and difficulty Hair loss Cold intolerance concentrating are sometimes the main Puffy eyes Underactive Thyroid symptoms. For a diagnosis, the physi- Decreased sweating If the gland is producing too little thy- cian will need to check thyroid hormone Infertility roid hormone (thyroxine), a person may levels with a blood test. Heavy menstruation To treat hypothyroidism (too little become easily chilled, sometimes running Lower libido lower-than-normal temperatures on a thyroid activity), doctors prescribe syn- Swollen hands or legs thermometer. Fatigue and constipation thetic hormone in pills such as Brittle fingernails are common complaints in this condition. Synthroid, Levoxyl or Levothroid Slow pulse Weight gain may result from inadequate to supplement or replace the patient's Anemia thyroxine, particularly due to increased inadequate supply. They used to be- Elevated cholesterol fluid retention. Thyroid deficiency can lieve there were no side effects to thy- Shortness of breath sap muscle strength and lead to shortness roid therapy if the dose was appropri- during exercise of breath during exertion. ate. But now scientists suspect that Hoarse voice thyroxine may increase the risk of os- Thick, dry skin, brittle fingernails and Clumsiness s coarse sparse hair are not unusual. When teoporosis, especially at higher than Depression Mental slowness the outer third of the eyebrows is missing, normal doses. This could be especially Carpal tunnel it strongly suggests low thyroid function. serious for older women, who are at syndrome Hair may also fall out on other parts of the the greatest risk of bone loss. CAN THYROID HORMONE WEAKEN BONES? Thyroid hormone has a profound effect on bone metabolism. People whose thyroid glands are overactive (hyperthyroidism) are at high risk of osteoporosis. Doctors have learned that when they give too much thyroid hormone to treat underactive glands, their patients also end up with weakened bones. Preliminary research has suggested that even normal doses of thyroid replacement hormone may lead to reduced bone density. This finding is unexpected and disquieting, but another report indicates that if thyroid therapy results in TSH values within the normal range, bone loss is minimized. Most recently, a study of older women found that long-term treatment with 200 micrograms or more of thyroid hormone was associated with lower bone mineral density. Postmenopausal estrogen therapy offset this bone loss. Under these circumstances, it makes sense to take care with the dose of thyroid hormone. This requires close communication and periodic testing. Age and other medications may affect the body's requirements for thyroid hormone. Bone density measurements may be called for, and if signs of osteoporosis begin to appear, preventive treatment may become prudent. References: Kung, A.W.C., & Pun, K. K. Bone Mineral Density in Premenopausal Women Receiving Long-term Physiological Doses of Levothyroxine. JAMA 1991;265:2688-2691. Greenspan, S. L., et al. Skeletal integrity in premenopausal and postmenopausal women receiving long-term l-thyroxine therapy. Am. J. Med. 1991; 91:5-14. Schneider, D.L. et al. Thyroid Hormone Use and Bone Mineral Density in Elderly Women: Effects of Estrogen. JAMA 1994; 271:1245-1249. © 2003 Graedon Enterprises, Inc.
  2. 2. SOME MEDICINES THAT AFFECT THYROID TESTS Drug Test Effect Amiodarone Total T4, serum T3, reverse T3 Raises T4, lowers T3 levels and increases rT3 Cordarone TSH and TSH. Abnormal tests may persist weeks or months after drug is discontinued. Drug may trigger thyroid function problems in some patients. Anabolic steroids Total T4, serum T3, TSH Lowers test values; levothyroxine dose may Testosterone, etc. need reduction Aspirin (large doses) Total T4 Lowers reading without affecting thyroid function Carbamazepine Total T4, T3 resin uptake, Lowers test values. In combination with other Tegretol others anticonvulsants, may affect thyroid Corticosteroids Total T4, serum T3, TSH Lowers test values Celestone Cortef Cortisone, etc. Estrogen Total T4 Raises reading without necessarily affecting Estrace thyroid function Estraderm Premarin, etc. Haloperidol TSH TSH scores tend to increase Heparin TSH TSH values may be low Iodine-containing All Thyroid function tests may be altered up to a contrast media few years after the x-ray or myelogram. Lithium All Readings may be altered indicating reduced Eskalith thyroid function. In some cases, thyroid Lithane function is suppressed. Lithobid, etc. Metoclopramide TSH TSH tends to be higher Reglan Oral Contraceptives Total T4 Raises reading without necessarily affecting Demulen 1/50 thyroid function Norlestrin Ovral, etc. Parkinson's disease TSH Test value lowered drugs Parlodel Sinemet Symmetrel Phenytoin (high dose) Total T4 Lowers reading without affecting thyroid Dilantin function Perphenazine Total T4 Raises reading without affecting thyroid Trilafon (long-term) function Propranolol (large T3, serum T4 Serum T3 decreases, serum T4 may increase doses >160 mg) without change in thyroid function Salsalate Total T4, serum T3, etc. Test readings are significantly lower; thyroid Disalcid function is not altered Tamoxifen Total T4 Raises reading without affecting thyroid Nolvadex function 2
  3. 3. NORMAL VALUES OF THYROID BLOOD Normal values may TESTS vary from lab to lab. Serum TSH by immunoradiometric assay (IRMA) 0.4-5 mcU/ml Total Serum T4 5-12 mcg/dL Serum T3 80-180 ng/dL T3 Resin Uptake 25-35 percent Conditions that Thyroxine-binding globulin capacity 15-25 mcg T4/dL May Require Change in Dose Aging Malabsorption Thyroid Testing that the thyroid gland is underactive, the Pregnancy doctor may order a TRH. This test utilizing Thyroid surgery Because the symptoms are non-specific, thyrotropin-releasing hormone is a way Treatment with diagnosis of thyroid disorders requires a of stimulating the pituitary gland to other drugs: careful history and sophisticated blood determine how it responds; a large Carafate test. The best test is one called an response to TRH suggests an underactive Cordarone immunoradiometric assay (IRMA). It thyroid gland. Dilantin measures the level of a brain hormone Many drugs can affect thyroid function Estrogen** called “thyroid stimulating hormone,” or tests. Make sure your doctor is aware of Iron TSH for short. Sometimes it may be all the medicines you are taking. This is Questran termed “thyrotropin.” especially important in the case of the Rifampin TSH controls the action of the thyroid radioimmunoassay (RIA) for serum total Tegretol gland the way a thermostat controls the T4 and the test for T3 resin uptake. * Testosterone activity of a furnace: when the gland is Although these older blood tests may still making too little thyroid hormone, the be done as part of a thyroid panel, brain puts out more TSH to tell it to make medications such as estrogen or Dilantin more. If there is too much thyroid hormone may alter their values and give misleading in the bloodstream, the brain's output of results. See the table on page 2. TSH will drop, sometimes almost to nothing. As a result, the TSH level is a very good, upside-down indicator of Pregnancy thyroid function: when you have too little thyroid hormone, TSH is high; if you have Just as estrogens in birth control pills * Wardle, Fraser & too much, TSH will be very low. A third- or postmenopausal hormone regimens Squire. “Pitfalls in the use generation sensitive TSH is most accurate. alter thyroid function tests, so does of thyrotropin concentra- Some experts recommend, however, that pregnancy. This can make an accurate tion as a first-line thyroid- total thyroxine be considered as well, to function test.” The Lancet assessment of thyroid function more 2001; 357:1013-1014. detect pituitary abnormalities.* difficult. Determination of free T4 may Should you be treated if your doctor also be needed to correct for the increase discovers an abnormal TSH level but you in blood protein that binds to thyroxine. have no other symptoms? This is TSH should not be affected in women controversial. People with subclinical with normal thyroid function, but many hypothyroidism may become who were being treated for thyroid **Arafah. “Increased symptomatic, but they may also do well problems before conceiving may need need for thyroxine in for years without treatment. Some experts higher doses of thyroxine during women with hypothy- believe treatment to normalize TSH pregnancy. TSH should be measured each roidism during estrogen protects other body systems from the therapy.” N. Engl. J. trimester so that appropriate thyroxine Med. 2001; 344: 1743- effects of hypothyroidism. replacement can be determined. 1749. If the TSH is within the normal range, Untreated hypothyroidism increases the but the person has symptoms suggesting risks for mother and baby. 3
  4. 4. “I had problems on Synthroid and switched to Armour. I am Natural or Synthetic? Balancing T3 and T4 now in excellent health with lots Underactive thyroid glands, or When a thyroid gland is func- of energy, a cheerful disposi- “hypothyroid” conditions, are tioning normally, it puts out two tion and greatly improved treated by supplying extra thyroid different hormones: triiodothyro- mental acuity and memory. I hormone. These hormones come in nine, or T3, and levothyroxine, also found it easy to lose 7 a wide variety of formulations. Natu- known as T4. (The numbers indicate pounds, which I could not do on ral products include the ground-up how many atoms of iodine are part Synthroid. dried thyroid glands of cows or pigs. of the hormone molecule.) Why, “Armour thyroid has both T3 This “desiccated” thyroid used to be then, do physicians prescribe only and T4, whereas Synthroid the only source of replacement hor- one, levothyroxine? Even in a provides only one of these and mone. It is still available as Armour healthy person, the thyroid gland the body is supposed to thyroid, but endocrinologists some- produces only a fraction of the T3 manufacture the other. Is it times worry about potency chang- that the body uses. Other tissues in possible some of us can’t make ing from one batch to the next. Con- the body normally convert T4 to the the other, so Synthroid doesn’t sequently, many doctors prefer to more active T3 as they need it, just work for us? I am living, prescribe a synthetic, usually by knocking one of the iodine atoms bouncing proof that a switch to levothyroxine, or T4. It is available off. This works well for most people. a natural thyroid can work.” generically or as Synthroid, Levo- But there are individuals for throid, Levoxyl or Unithroid. whom levothyroxine just doesn't Levothyroxine comes in a wide seem to do all it should. These people range of doses. The doctor generally continue to experience symptoms “For years I took Thyrolar for hy- tries to adjust the dose so that each even on doses of levothyroxine that pothyroidism. When I had to patient is taking the smallest should be adequate. Such patients change doctors, my new endo- amount that brings the TSH level may complain that their previous crinologist refused to prescribe into the normal range. Generally, experience with Armour thyroid was it. He said the dose is too hard to hormone specialists recommend far better and wonder why the phy- adjust and test results difficult to starting at a very low dose and sician does not simply prescribe interpret. Instead he prescribed gradually increasing to the desired dessicated thyroid. Because Armour Synthroid. level. This requires patience and thyroid contains both T3 and T4, “In the three years since then, I persistence as well as good commu- some endocrinologists, such as Dr. have gained 25 pounds and am nication with the doctor and peri- Ridha Arem, are prescribing it in tired all the time. I have com- odic monitoring. Some people may conjunction with levothyroxine for plained and had numerous blood need dose reductions as they age, patients who may not be converting tests, but each time the results especially if they develop heart prob- T4 efficiently and who continue to are within normal range. A nutri- lems. experience symptoms. Dr. Arem tion expert said I should be taking Levothyroxine is absorbed best if cautions that a single dose of Armour Armour Thyroid because it is taken on an empty stomach, so during the day may result in an Synthroid robs the bones of cal- doctors often recommend it be taken initial surge of T3 and then a drop in cium. at least a half-hour before break- the level of this hormone later in the “When I asked the doctor about fast. It is particularly important not day. It does not last long. this, he said Synthroid is best to swallow this thyroid hormone at Other experts have found that because the dosages are exact the same time or within an hour of adding a small amount of T3 to pa- and testing is more precise. calcium or iron supplements. These tients’ levothyroxine can alleviate Those nice normal test results minerals can prevent absorption of depression and mental cloudiness make my doctor feel good but I the hormone. The most important from low thyroid hormone better still feel lousy.” thing is to be consistent in the way than T4 alone. It is possible that you take it, so that once the proper some of these people are not capable dose has been determined, that is of converting T4 to T3 efficiently. In the dose you actually get. Many one study, researchers found the *Bunevicius, Kazanavicius, experts feel it’s best to stick with dose of levothyroxine that normal- Zalinkevicius and Prange. “Effects of the same brand rather than switch- ized TSH. Then, they replaced 50 Thyroxine as Compared with Thyroxine Plus Triiodothyronine in Patients with ing back and forth, because there mcg of that dose with 12.5 mcg of T3, Hypothyroidism.” N. Engl. J. Med. may be some differences in formu- sold in this country under the brand 1999; 340: 424-429. lation that alter absorption. name Cytomel.* 4
  5. 5. Dr. Arem writes that his experi- Treating Overactive ence with a T4/T3 combined regimen has been favorable, especially for Thyroid Glands patients who also have depression An overactive thyroid gland that or fibromyalgia. He advocates di- produces too much hormone can be viding a small dose of T3 even fur- just as bad for health as one that ther, so that it can be taken two or doesn't produce enough. Hyperthy- three times a day. roidism, or thyrotoxicosis, may pro- Not all patients require T3 in ad- duce psychological symptoms, es- dition to standard levothyroxine pecially insomnia, nervousness or (T4). And for some endocrinologists, anxiety, in addition to physical the idea of using Armour thyroid, symptoms like excessive sweating, Symptoms of alone or in combination with rapid heart beat, inability to stand High Thyroid levothyroxine, smacks of quackery, heat, frequent bowel movements, Activity or at best fringe medical practice. increased systolic blood pressure or But perhaps more doctors will be- wide pulse pressure, missing or Fatigue gin to experiment in collaboration scanty menstrual periods, and fin- Insomnia with patients who continue to suf- ger tremor. The TSH level in a case Weakness fer symptoms of low thyroid despite of thyrotoxicosis will be very low. Nervousness TSH readings in the normal range. Even the very sensitive IRMA test Palpitations Too often such people are told, in for TSH may not be able to detect it. Heat intolerance essence, that their troubles are all The most common form of hyper- Eye complaints in their heads. It is very likely that thyroid condition is Graves’ disease. psychological factors do contribute This is an immune system malfunc- Increased sweating to problems such as lethargy in some tion in which the body produces Light menstruation instances. Both doctors and patients antibodies that attack the parts of Loose or soft nails should keep in mind, however, that the thyroid gland that usually de- Irritability a thyroid imbalance can sometimes tect and attach to TSH. This gives Rapid pulse trigger such psychological problems the gland a false signal that more Irregular heartbeat as depression, feelings of low self- thyroxine is needed and it keeps on Finger tremor worth, or anxiety. producing more, in a “sorcerer’s Shortness of breath apprentice” scenario. In other cases, Frequent bowel hyperthyroid conditions may result movements Side Effects from growths on the thyroid (thy- Decreased There shouldn't be any obvious roid nodules). Diagnostic procedures concentration side effects of thyroxine when the like ultrasound, CT scan or mag- netic resonance imaging (MRI) may Weight loss dose is properly adjusted. In some- be needed if nodules are suspected. Fine, soft hair one with heart problems, the dos- Because excess thyroid can lead to Hair loss age should be increased very gradu- ally. If levels are too high, adverse bone loss, patients who have been Anxiety reactions such as heart palpitations diagnosed as hyperthyroid should Increased libido and rapid heart beat, insomnia, ner- also be followed up with bone den- Increased appetite vousness, and higher blood pres- sity measurements. Increased blood sure may result. Other possible signs The person with Grave's disease pressure of overdose include headache, diar- should also see an ophthalmologist rhea, tremor, increased sweating, for regular eye examinations, be- changes in appetite, weight loss and cause as many as half of those with reduced menstrual flow. Report such Graves’ disease develop inflamma- symptoms to your physician tion in the muscles and other tis- promptly, as continued overdosage sues surrounding the eyes. Symp- may cause serious cardiac or ner- toms such as redness, soreness, vous system complications. If you blurred vision, bulging eyes and continue to have symptoms of low aversion to light may all be related thyroid activity, tell your doctor. to this autoimmune condition. 5
  6. 6. Treatment of thyrotoxicosis can be surgery is less commonly recommended complicated. Doctors must choose be- for adults except in the case of certain tween surgery, radiation or thyroid-sup- large nodules or in the case of cancer. We heard a tragic pressing drugs such as Tapazole (me- Look for a surgeon with plenty of experi- story from a mother thimazole) or propylthiouracil. Each ence. whose 26-year-old form of therapy has its advantages and When treatment for overactive thy- daughter was being drawbacks, and must be tailored to the roid is begun, a beta-blocker like Inderal treated for an overac- individual patient. (propranolol) may be used to treat un- tive thyroid gland. She Radioactive iodine is usually the treat- comfortable symptoms such as palpita- was given Tapazole ment of choice for Graves’ disease. Io- tions or rapid heart rate, tremor and (methimazole) to dine concentrates in the thyroid gland, anxiety. This medicine will not correct suppress her thyroid, and delivers its dose of radiation there the thyroid problem, though, so thyroid but she was not told where it is needed. This treatment de- treatment is also needed. that this drug could stroys thyroid gland tissue and as a reduce her ability to consequence, it is irreversible. If there is Drug Interactions fight infection by any question about the accuracy of the reducing her produc- diagnosis, a different therapy might be There are a number of medicines that tion of white blood preferred. In addition, most people can interact with thyroid hormone supple- cells. treated with radioactive iodine for mentation. Abnormal levels of thyroxine Despite a clear warn- Graves’ will eventually become hypothy- in the blood can affect the metabolism of ing in the prescribing roid. Like other hypothyroid people, they asthma medicines like theophylline information to have will need to take thyroxine to supply the (Bronkodyl, Slo-Phyllin, Theolair, patients report sore etc.) or aminophylline. Other drugs that hormone their thyroids cannot make. throat, fever or other The thyroid-suppressing drugs me- interact are listed opposite. symptoms of infection, MEDIC thimazole and propylthiouracil are fre- Lithium (Eskalith, Lithane, this young woman was Lithobid, etc.), used to treat manic-de- quently used to treat hyperthyroidism. MEDICINES sore treated for many The THYROID HORMONE amount pressive disorder, can throw the thyroid CAN dose is adjusted to the lowestWEAKEN BONES? throats, strep infec-MEDICINES THAT AFFECT T and T levels. gland out of kilter, causing enlargement that results in normal 3 tions, tonsillitis and THYROIDTESTS 4 Methimazole is usually taken once a (goiter), hypothyroid or, rarely, hyper- gingivitis without a day, so it is more convenient. However, thyroid conditions. Occasionally the heart blood test. The doctor for pregnant or nursing women, drug amiodarone (Cordarone) will sup- treating her failed to propylthoiuracil (taken three times press the thyroid gland so that treat- connect her series of daily) is considered preferable. (Radio- ment is needed. Aredia (pamidronate), infections with an active iodine treatment is inappropriate for abnormal calcium metabolism, may adverse effect of her during pregnancy, as it may affect the also alter the thyroid gland's equilib- treatment for Graves’ MEDICINES THAT AFFECT THYROID TESTS with your pharmacist and infant’s thyroid gland.) Side effects of rium. Check disease. When she the medications include bitter taste and doctor to make sure any medicine you are finally was admitted to nausea. Skin rash, joint pain or an in- taking is safe in combination with your the hospital with crease in temperature may indicate a thyroid hormone. stomach ache, dizzi- serious reaction; the doctor should be Never discontinue a thyroid hormone ness, vomiting and notified promptly. Methimazole occa- medication, regardless of which one you fever, she had a sionally suppresses infection-fighting take, without your physician’s supervi- severe infection and white blood cells, leading to a series of sion. Most people diagnosed with a thy- no white blood cells. sore throats or other infections. If this roid problem need treatment for the rest She died the next day. problem is not detected in time to re- of their lives. verse it, the patient may die. Some people recover from hyperthyroid conditions Thyroid Treatment in Older after a year or two of thyroid-suppress- ing medication, but no thyroid treat- People ment should be discontinued without Thyroid conditions in older adults may close medical supervision. be more difficult to detect. For one thing, Surgery to remove excess thyroid tis- some of the symptoms of an underactive sue is another possible treatment. It thyroid, such as fatigue, forgetfulness or requires careful presurgical treatment. constipation, may be accepted by patients Although complications are uncommon, and families alike as inevitable signs of 6
  7. 7. aging. So might the palpitations, ner- category of “subclinical hypothyroid- Thyroid and Iron vousness or weakness that may be caused ism.” Millions of people take by excessive thyroxine. The question of whether these people Synthroid daily, but tak- Sometimes older people have unusual should be treated is extremely contro- ing 300 mg of the iron symptoms. Too much thyroid hormone versial. Experts agree that if there are supplement ferrous sul- can cause loss of appetite, congestive symptoms of an inactive thyroid, treat- fate at the same time can heart failure, depression, dementia, apa- ment with the lowest effective dose of reduce the effectiveness thy, constipation or muscle rigidity in thyroxine is appropriate. Some elderly of levothyroxine. elderly persons. Hair loss involving body people with no initial symptoms even- Blood tests showed less and even pubic hair may not be men- tually develop obvious hypothyroidism thyroxine circulating in the tioned or recognized as a possible symp- that requires treatment. It is crucial blood stream. Patients tom of hypothyroidism. The clinical pic- not to overtreat the elderly, because who took Synthroid with ture can be so different from the “text- heart disease and osteoporosis could iron also had more symp- book” picture of thyroid disease that the both be made worse by overzealous thy- toms of hypothyroidism, condition might not even be suspected. roid treatment. Older people also seem such as fatigue, menstrual Thyroid function tests may show el- to metabolize thyroxine more slowly, irregularities and chilling. evated levels of TSH in older people even and may need lower doses initiated more The researchers suggest when they don't seem ill. In some cases, gradually than younger patients. This that “separating the times levels of free T4 are normal. One study is especially important if a person al- at which the two drugs are discovered around 15 percent of both ready has some heart disease and is ingested by 2 or more men and women over 60 fell into this taking a medication like digoxin. hours” might limit this in- teraction. [Campbell et al. “Ferrous SOME DRUGS THAT INTERACT WITH THYROID HORMONE Sulfate Reduces Thyroxine Efficacy in Patients with Hypothyroidism.” Annals of Internal Medicine 1992; Aminoglutethimide Long-term treatment reduces T3, T4 and raises 117:1010-1013.] Cytadren TSH Antacids AME M Aluminum or calcium-containing antacids may Thyroid and interfere with absorption, reducing effectiveness Androgens Calcium testosterone, Androgens increase the effects of thyroxine. Few studies have been Halotestin, Testred, etc. Lower dose (25-50%) may be needed.* done to determine if cal- Antidepressants cium supplements inter- Elavil, Tofranil, Thyroxine increases antidepressant act with levothyroxine to and other tricyclics action; more side effects from both drugs. reduce its absorption. Three cases have been Paxil, Prozac Rare reports of thyroid dysfunction Asthma medicine reported of women whose aminophylline, theophylline Hypothyroid people metabolize these thyroid pills (Levothroid, drugs slowly; with thyroxine, they may need a Synthroid) became less higher dose of asthma drug. effective, as measured by Blood thinners blood tests and clinical Coumadin Anticoagulant action is increased by symptoms, when they thyroxine; dangerous bleeding possible. were taken at the same Cholesterol medicine time as calcium carbon- Colestid, LoCHOLEST, These drugs may reduce thyroxine absorp- ate (Os-Cal and Tums). Questran, Welchol tion. Take at least 4 hours apart. It’s a good idea to take Diabetes medicine Thyroxine replacement lowers effectiveness. these two pills four hours Epilepsy drugs apart. Dilantin, Tegretol These may increase thyroxine requirements. [Schneyer. “Calcium Heart drugs carbonate and reduction of levothyroxine efficacy.” JAMA Beta blockers An increase in thyroxine may decrease the 1998; 279:750.] effectiveness of these medicines; beta-blockers may reduce T4 to T3 conversion Digoxin (Lanoxin) Blood levels of digoxin decrease as levels of * *Arafah. “Decreased thyroxine increase. Levothyroxine Requirement in Women with Hypothyroidism Interferon alfa Long-term use may lead to thyroid antibodies and during Androgen Therapy for Intron A thyroid malfunction. Breast Cancer.” Ann. Intern. Med. Niacin, slow-release T4 and thyroxine-binding globulin (TBG) may drop 1994;121:247-251. 7
  8. 8. Thyroid Problems in for years. Occasionally people with ac- Children cess to thyroxine will even try to treat Thyroid Fighting themselves for such problems, but get- Because thyroid hormone is cru- Foods? ting thyroid hormone you don’t need cial for growth and development, isn’t good for you and can cause signs of Certain foods contain a babies are now screened at birth to hyperthyroidism. To determine if you chemical that can block make sure their levels are adequate. truly need thyroxine that may have been thyroid hormone. A diet In parts of the world where iodine is prescribed originally for unclear reasons, that relies heavily on one scarce, cretinism affects some vul- the doctor may ask you to stop treat- or more of these can result nerable children who end up with ment, and then do a blood test after four in the development of a inadequate thyroid hormone in the weeks. If all blood tests are normal at goiter, in which the thyroid womb and from infancy onward. In that point, the doctor may decide thyrox- gland grows larger in an the United States, cretinism has ine is unnecessary. attempt to make more become a rarity since the introduc- thyroxine. tion of iodized salt, which provides Natural Treatments There is no evidence that an ample amount of iodine in food Many people would like to find an herbal these foods interfere with everywhere in the country. medicine that would correct thyroid im- thyroid treatment when Neonatal screening discovers the balance naturally. Although some plant eaten in normal amounts, one baby in 4,000 born without substances can change thyroid function, but prudence would enough thyroxine. Treatment with the results are unpredictable. The resin suggest moderation in replacement hormone wards off the guggul from India, used to lower choles- consuming: physical and mental stunting that terol, is reputed to increase thyroid hor- broccoli might otherwise occur. A baby with mone production, but its utility in treat- brussels sprouts severe untreated hypothyroidism ing hypothyroidism is not known. cabbage may lose three to five IQ points Some people attempt to treat thyroid cauliflower within the first year of life. In chil- problems with natural sources of iodine millet dren who develop thyroid insuffi- such as seaweed. Although some iodine mustard greens ciency after babyhood, one of the is crucial, large doses of iodine can be peanuts earliest signs may be a change in harmful. radishes the growth curve. This is one of The best way to use a more natural rutabaga several reasons for keeping track of approach to thyroid treatment may be to soybeans a child’s weight and height. As for integrate Armour thyroid with a syn- turnips adults, treatment requires finding thetic levothyroxine, as described on page the appropriate dose of thyroxine, 4. This poses a dilemma for the vegetar- based on TSH tests. ian, however. Armour is derived from For More Information: Children may also develop Grave’s animal sources. In addition, relying The Thyroid Foundation of disease, although this is very rare heavily on soy as a primary protein source America, Inc. in young children. Parents may no- can also put a strain on the thyroid. A Ruth Sleeper Hall, Rm. 350 tice emotional disturbances more prudent limit is three or four servings of 40 Parkman St. than the physical symptoms typical soy per week. Boston MA 02114 of hyperthyroid conditions in adults. The minerals selenium (50 mcg) and Phones: Treatment may differ, too, as the zinc (15 mg) are important for thyroid (800) 832-8321 long-term safety of radioactive io- health. If the diet does not contain good (617) 726-8500 dine treatment in children has been sources of these, such as whole grains, questioned. As a result, doctors are fish, lean beef or soy, a supplement is Web site: more likely to recommend thyroid- recommended. suppressing drugs or surgery for children or adolescents diagnosed If you have questions or comments, Recommended Reading: with Grave’s disease. feel free to write: The Thyroid Solution Other Reasons for Graedons’ People’s Pharmacy by Ridha Arem, M.D. P.O. Box 52027 Ballentine Books, 1999. Thyroid Treatment Durham, NC 27717-2027 In the past, doctors sometimes pre- You may also wish to order a CD of our The Thyroid Book scribed thyroid hormone for condi- interview with Dr. Ridha Arem: Call by Martin I. Surks, M.D. tions such as obesity or chronic tired- (800) 732-2334 and request show Consumer Reports, 1993. ness, but this has been discouraged #393. The cost of $15 includes ship- ping & handling. 8