Keys to Taking Thyroid Medication Correctly

Instructions for taking thyroid hormone replacement drugs like Synthroid (levothyroxine) and Cytomel (liothyronine/T3) are very specific for good reason. Taking your thyroid medication the right way can influence how well your body absorbs it. And failing to get the full dose of your medication can throw your hormone levels out of balance.

It's important to understand your thyroid medication so you can effectively manage your thyroid disease. This way you can ensure that you're doing all you can to help your hormone replacement drug do its job properly.

This article will discuss the need-to-know facts about thyroid medication. It will also provide tips on what you can do to take your thyroid medicine the right way.

Be Consistent

Hypothyroidism is, in most cases, a lifelong condition that must be strictly managed. It's important to take your prescribed dosage every day—and at the same time each day.

You also want to be consistent about other issues. For example, you need to remember if you should take your medication with or without food. You also need to remember if you're supposed to take your medication before or after starting or stopping a high-fiber diet. Talk with your doctor to learn what you should do about these issues.

Some people find it difficult to get into a daily routine with their thyroid medication. Keeping your medication in the same place all the time may help. Setting an alarm on your cell phone may also help you remember to take your dose at the right time.

Continue to Take Your Medication

Some people decide to go off their thyroid medications altogether without talking to their doctor. This can be particularly dangerous if you have a surgically removed or radioactive-ablated thyroid. It's also dangerous if your thyroid is atrophied or underactive due to Hashimoto's disease.

When you don't take your thyroid medications, you may not only experience symptoms of hypothyroidism but see a rise in your cholesterol and even your risk for heart disease.

In the past, some people believed that decreasing the dose of thyroid replacement might reduce the risk of heart-related issues. But the opposite may actually be true.

While taking too much thyroid replacement medication is unhealthy, taking a lower-than-needed dose is not safer than taking the dose that normalizes your thyroid tests.

Pregnancy and Breastfeeding

Some women mistakenly think that thyroid hormone drugs are dangerous to a baby during pregnancy or breastfeeding. As a result, they wonder if they should stop breastfeeding their baby.

The opposite is actually true. Taking the appropriate dose of thyroid medication is essential for a healthy pregnancy and baby. And most often, thyroid hormone doses need to be increased when a woman learns she is pregnant.

If you feel nervous about taking medication during pregnancy, keep in mind that you are simply replacing a hormone that your body is not making in adequate amounts.

Eat at the Right Time After Your Dose

Ideally, you should take your thyroid medication in the morning and wait 30 minutes to an hour before eating. (If you absolutely must eat sooner than that, make sure you do this consistently.) This helps ensure that the drug is properly absorbed in the intestine so you get your full dose.

That said, some foods should only be eaten at least three to four hours after thyroid medication. Examples include calcium-enriched foods such as high-calcium orange juice and Greek yogurt, as well as fiber-rich foods.

Are Goitrogenic Foods a Problem?

Goitrogens are substances found in some foods that may have an anti-thyroid effect. However, experts don't agree on whether foods such as cruciferous vegetables can interfere with the overall effectiveness of your treatment.

Examples of foods that are highly recommended as part of a healthy, cancer-prevention diet include:

  • Broccoli
  • Cauliflower
  • Cabbage
  • Kale
  • Berries
  • Green tea

You shouldn't try to completely avoid these foods, but you may want to spread them out so you aren't eating large amounts during any single meal. The same appears to be true with soy foods. Eating them in moderation when you have thyroid disease appears to be key.

Don't Drink Coffee With Your Thyroid Medication

Coffee can also interfere with the way your body absorbs thyroid medication. If you can't wait an hour to have your early morning coffee, there are a few options you may wish to discuss with your doctor. Coffee doesn't seem to affect Tirosint, a gel-capsule or liquid form of levothyroxine.

If you are taking a different brand of levothyroxine and don't want to change, you can also talk to your doctor about whether you should take your thyroid medication at bedtime.

Consider Other Medications You're Taking

Like food, other medications should be taken at least an hour after you take thyroid medications. This will help avoid any problems with absorption. But with some drugs, waiting even longer is important. For example, you should wait at least four hours before or after taking thyroid replacement medications before using antacids.

There are many medications that can interact with thyroid hormones, either increasing or decreasing the amount available to your body. Common examples include:

drugs that may interfere with thyroid medication

Verywell / Emily Roberts

HRT and Birth Control

Women taking estrogen—hormone replacement therapy (HRT) or the birth control pill—may need more thyroid replacement hormone. Estrogen increases the body's production of a protein that makes thyroid hormone inactive.

To compensate for this, the dose of thyroid hormone may need to be increased slightly. After a woman starts or stops taking oral contraceptives or hormone replacement therapy, the doctor should test their thyroid levels to determine if it is affecting how the thyroid works.

Be sure that the doctor prescribing your thyroid medication and monitoring your thyroid disease is aware of these and any other drugs you are taking.

Be Careful When Switching Brands of Levothyroxine

Brand-name levothyroxine is typically consistent, in terms of potency, from refill to refill. That is not always the case, however, with different generics.

For some people, 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.

If you do switch medications, either brand names or generics, it's important to follow up with your doctor to have your thyroid tested. This is usually done six weeks after the change is made. Then the doctor should check it about every six weeks thereafter until your levels are stable.

Don't Assume "Normal" Labs Means Your Dose Is Optimal

While the reference ranges for thyroid tests often give a thyroid-stimulating hormone (TSH) range of 0.4 to 5.0, the fact that 95% of people without thyroid disease have a TSH between 0.4 and 2.5 has led some researchers to believe a goal TSH in this range may be optimal.

Talk to your doctor about what the optimal TSH level is for you as an individual and whether or not your current thyroid hormone replacement medication needs to be adjusted.

A person who continues to have hypothyroidism symptoms with a high-normal TSH, for example, may benefit from getting their TSH closer to 1.0.

Also note that, for some people, it may be a good idea to check additional thyroid tests, such as T4, free T4, T3, free T3, and thyroid autoantibodies even if TSH is normal.


Taking your thyroid medicine the right way can help your body effectively absorb it. Consistently taking it at the right time as well as avoiding food too soon after taking it are all important things you should remember.

It's also important to be careful when taking other medications along with thyroid medication. And if you switch brands or generic manufacturers, you may need to get your thyroid levels tested.

A Word From Verywell

If you're not careful, you can end up getting less thyroid medication than you need. Check with your doctor to make sure you are on a dose that is ideal for you to begin with. In addition, the dose of thyroid hormone that you require can change at different times in your life.

Paying attention to any symptoms you are experiencing can give you clues as to whether you may be overmedicated or undermedicated. Symptoms, after all, are our bodies' way of alerting us that something's not right.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  4. Bajaj JK, Salwan P, Salwan S. Various possible toxicants involved in thyroid dysfunction: A reviewJ Clin Diagn Res. 2016;10(1):FE01-FE3. doi:10.7860/JCDR/2016/15195.7092

  5. Cappelli C, Pirola I, Gandossi E, et al. Thyroid hormone profile in patients ingesting soft gel capsule or liquid levothyroxine formulations with breakfast. Int J Endocrinol. 2016;2016:9043450. doi:10.1155/2016/9043450

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Additional Reading

By Mary Shomon
Mary Shomon is a writer and hormonal health and thyroid advocate. She is the author of "The Thyroid Diet Revolution."