Taking Your Thyroid Medicine Successfully

Q: On my thyroid medicine bottle, there's an additional label that says to take it in the morning on an empty stomach. Sometimes I forget to take it before breakfast. Is it okay to take it later?

You’re not alone in asking about this. The synthetic thyroid hormone levothyroxine is the most prescribed medication in the United States. My mother was always worried about what might happen if she didn’t take her thyroid medicine "correctly." Taking her first bite of breakfast, if she saw her yellow levothyroxine tablet still waiting on the counter, she’d skip her dose that day.

“Louise, what if it can’t be safely mixed with food? Could it start a chain reaction in my stomach?”

“Mom, if you do forget to take your thyroid medicine before you eat breakfast, the worst that could happen is your body won't get the full dose. That’s because food can change how much of the levothyroxine your body can take in.

Taking it with breakfast gives you a lower dose, but skipping it guarantees you get none of your dose. Taking no thyroid medicine at all affects you more than accidentally taking it with food."

My mother wasn’t the only one.

85-year old Ellen would set her alarm for 5 am every day to take her levothyroxine in the morning an hour before having breakfast. That's because otherwise, she’d forget about it altogether.

Ellen took medicines four times daily. She’d start with levothyroxine at 5 am, take her morning pills with her breakfast, a blood thinner medicine at 5 pm, and her cholesterol medicine at bedtime. She was taking her medication 4 times a day, which felt overwhelming.

“I want to take my medicines correctly, but it’s so hard to remember to take all of them the way I’m supposed to.”

I suggested she take her usual morning medicines at breakfast, then take her thyroid medicine, the blood thinner, and cholesterol medicine together at bedtime. That way, she only had to remember to take pills twice a day.

Within 2 weeks of taking her thyroid medicine at night, her improved consistency was paying off. Ellen told me she felt less overwhelmed and more energetic. Just as importantly, she no longer worries about taking her medicine correctly.

"It's such a relief to have less to remember and wonderful to have more energy!”

Your body processes and metabolism are controlled by the level of active thyroid hormone in your body. Your thyroid gland secretes a form of thyroid hormone called T3 or liothyronine into your bloodstream.

Most of your T3 needs to be converted to active thyroid hormone, called T4, in your tissues by specialized proteins called enzymes. Levothyroxine is a synthetic version of T4 that can be taken once daily.

Your doctor monitors your thyroid hormone level by checking the amount of TSH in your blood. If TSH is too high, your body needs more thyroid hormone, and if TSH is too low, you need less. This may seem backward, but TSH is just a messenger, not thyroid hormone itself. Your doctor may also check your T4 level.

If your TSH blood level is elevated or your T4 level is low, you need more levothyroxine (synthetic T4). Checking TSH 4-6 weeks later will confirm whether your thyroid hormones are back to normal.

5 Ways To Getting the Most Out of Taking Levothyroxine:

1. Be consistent.

Levothyroxine is absorbed better if you take it on an empty stomach (30 minutes to an hour before a meal or 4 hours afterward). If you take it the same way every time, however, you’ll get a consistent dose, and your thyroid level will be more stable.

2. Avoid taking levothyroxine with coffee or tea.

Coffee and tea can decrease how much levothyroxine you absorb by nearly 30%. If possible, wait an hour after taking your thyroid supplement for your first cup of joe.

3. Don’t skip your dose.

Even if you forget to take it at your usual time, absorbing some of your thyroid supplement every day is far better than getting none.

4. Space out any mineral supplements.

Some minerals interfere with levothyroxine absorption, including calcium, iron, aluminum, and multivitamin supplements containing those minerals.

One solution is taking any multivitamin and mineral supplements later in the day, at least 4 hours before and after your levothyroxine. You can safely take multivitamins without any minerals with levothyroxine.

5. Try taking levothyroxine at bedtime.

If you avoid eating for 4 hours after your evening meal, bedtime can be an ideal time to take levothyroxine.

Dr. Louise Achey, Doctor of Pharmacy, is a 40-year veteran of pharmacology and author of Why Dogs Can’t Eat Chocolate: How Medicines Work and How YOU Can Take Them Safely. Get clear answers to your medication questions at her website and blog TheMedicationInsider.com. ®2021 Louise Achey