Common Thyroid Medication Mistakes

Even slight changes in how you take thyroid hormone can alter absorption

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If you are taking a thyroid hormone replacement drug like levothyroxine (Synthroid, Levoxyl, Levothroid, Unithroid, Tirosint), liothyronine/T3 (Cytomel, compounded), or natural desiccated thyroid drugs (Armour, Nature- thyroid), you may be making one of these common mistakes. Even slight changes in how you take your medication can influence how well your body absorbs it.

It's crucial to avoid medication errors in order to ensure that you get the full dose of your medication, or else your thyroid hormone levels will be thrown out of balance. Here are some of the most common thyroid medication pitfalls to avoid. 

Not Taking Your Medication at All

Some patients decide, without their doctor's approval, to go off thyroid medications entirely. This can be dangerous if you have a surgically removed or radioactive ablated thyroid, or if your thyroid is atrophied or underactive due to Hashimoto's disease. Read more about patients who refuse to take their thyroid medication.

Inconsistency in How You Take Your Medication

One of the keys to success with thyroid medication is consistency. That means, taking your prescribed dosage, daily, at the same time each day. You also want to be consistent about other issues, such as whether you take your medication with or without food, and before or after starting/stopping a high-fiber diet.

Missing Doses of Thyroid Medication

If you have trouble remembering to take your thyroid medication, you are not alone. Some people find it difficult to get into a routine of taking thyroid medication daily and at the same time each day. Here are ten creative ways to remember to take your thyroid pill.

Switching Brands of Levothyroxine

For some patients, the variation in consistency from one maker of generic levothyroxine to another can have a negative impact on proper thyroid replacement. If you have this experience, you may want to ask your doctor about writing a "dispense as written/no substitutions" prescription for a brand name levothyroxine.

Taking Calcium or Calcium-Rich Foods Too Close to Your Thyroid Medication

Be careful about taking calcium supplements, calcium-fortified orange juice, and high-calcium foods (i.e., Greek yogurt) at the same time as thyroid hormone. Allow at least 2 to 3 hours apart from your thyroid medication, so that absorption is not impaired.

Drinking Coffee With Your Thyroid Medication

Coffee can interfere with the absorption of your thyroid medication. So if you want to drink your morning coffee, take your medication, and wait at least an hour before drinking coffee. (Note: the levothyroxine drug Tirosint, a liquid-cap form, appears to be unaffected by coffee, and may be able to be taken together.)

If you must have your coffee first thing, or you need to eat in the morning or take calcium and iron supplements in the morning, you may want to discuss with your doctor whether to take your thyroid medication at bedtime. This can help aid in the effective absorption of your medications.

Eating High-Fiber Foods or Taking Fiber Supplements Too Close to Your Thyroid Medication

Be careful about eating high-fiber foods, or taking fiber supplements, with your thyroid medication. The fiber can impair the absorption of your thyroid medication.

Taking Thyroid Medication Too Close to Other Medications

You need to be careful about taking thyroid medications along with other medications. For example, you should not take antacids within two hours of thyroid hormone. Allow at least two to three hours between your thyroid medication and antacids, so absorption is not affected. Watch for interactions with antidepressants and thyroid hormone. Zoloft, Paxil, and Prozac, for example, can make thyroid medications more or less effective, and may mean you need a dosage change in your thyroid medication. Proton pump inhibitor drugs like esomeprazole and omeprazole -- which are taken to combat stomach acid -- can also impair absorption of thyroid medication.

Stopping Your Medication While Pregnant or Breastfeeding

Some women mistakenly think that thyroid hormone drugs are dangerous to a baby during pregnancy or breastfeeding. The opposite is actually true. Taking the appropriate dose of thyroid medication is essential for a healthy pregnancy and baby. Don't stop taking thyroid hormone when you're pregnant or breastfeeding.

Eating With Your Thyroid Medication

Ideally, you should take your thyroid medication in the morning, and wait an hour before eating. (Conversely, if you absolutely must eat, make sure you do this consistently, and you should still should put three to four hours between your thyroid medication and iron, calcium and fiber-rich foods.)

Taking Estrogen Therapy Without Checking Thyroid Levels 

Women taking estrogen—hormone replacement therapy or the birth control pill—may need to more thyroid replacement hormone. The reason? Estrogen increases the body's production of a protein that binds thyroid hormone, making it inactive. This can cause a need to increase the dosage of thyroid hormone slightly. After beginning any estrogen therapy, have thyroid levels tested to see if estrogen is having an impact on thyroid function.

Not Knowing About Synthroid's Allergenic Fillers

Synthroid tablets are made with two ingredients—acacia and lactose—that can trigger allergies in some people. Some people who have pollen allergies and hay fever—especially to tree and grass pollens—may also have an allergy to acacia, which is found in Synthroid's formulations. And lactose can trigger symptoms in people with lactose intolerance, which is the inability to digest lactose, a major sugar found in milk. For those patients with these allergies, the hypoallergenic, liquid-cap, drug Tirosint, which has no fillers or dyes, may be a better option.

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