Can I take levothyroxine at night?

In this article:

• Levothyroxine at night
• What happens when you take levothyroxine at night?
• How to switch from morning to nighttime doses
• The bottom line

In this article

• Levothyroxine at night
• What happens when you take levothyroxine at night?
• How to switch from morning to nighttime doses
• The bottom line

Levothyroxine sodium (brand name Synthroid) is a thyroid medication commonly prescribed for the treatment of hypothyroidism. This condition occurs when your thyroid gland doesn’t produce enough thyroxine (a thyroid hormone). It helps bring thyroid-stimulating hormone (TSH) levels back to the normal range, with the goal of restoring normal thyroid hormone levels throughout the body. This helps to regulate your energy, metabolism, and overall health. Generally, people take levothyroxine in the morning on an empty stomach, but could taking it before bed offer similar, or even better, results?

You can take levothyroxine at night—but it’s not the right choice for everyone. Keep reading to learn the pros and cons of morning levothyroxine intake versus evening doses and how taking levothyroxine at night can impact the absorption of the medication and your quality of life.

Can I take levothyroxine at night?

The short answer is yes, you can take levothyroxine at night. It won’t change the medication’s efficacy—as long as you take it consistently and on an empty stomach. A recent randomized crossover trial found no significant difference in TSH levels or thyroid hormone levels when levothyroxine is administered at bedtime versus in the morning.

Some people with variable schedules find it easier to remember to take levothyroxine before bed. Just remember to wait at least three to four hours after your last meal.

What happens when you take levothyroxine at night?

Insomnia, or trouble falling or staying asleep, is a potential side effect of levothyroxine. Hence, taking a dose at bedtime could make sleeping difficulties worse.

Other side effects of levothyroxine may negatively affect sleep, such as headache, shortness of breath, nervousness, irritability, and tremors—particularly if your dose is higher than needed to manage your condition.

Yet, for people who don’t experience side effects, taking a nighttime dosage may help avoid a food or drug interaction.

How to switch from morning to nighttime doses

Switching from morning to nighttime doses of levothyroxine requires careful coordination with your healthcare provider and pharmacist because this medication has several potential food and drug interactions. “Patients should consider their daily routine, how consistent they are with timing, and any potential interactions with food or medications,” explains Kimberly Langdon, MD, a healthcare provider in Ohio. By following these steps, it’s possible to transition from morning doses to taking levothyroxine at night:

1. Consult with your healthcare provider

Before making any changes, consult with your thyroid treatment team to ensure that switching to nighttime administration won’t disrupt your thyroid function. Your healthcare provider will likely schedule blood tests to monitor how well your body adjusts, particularly your serum TSH levels. Any irregularities in your thyrotropin or thyroxine levels might indicate the need for an adjusted dose.

2. Take on an empty stomach

Taking levothyroxine on an empty stomach is critical to ensuring your body absorbs the medication properly, whether you choose morning or bedtime administration.

Food interactions

Food can significantly reduce the drug’s intestinal absorption, leading to fluctuating thyroid hormone levels and potential side effects, such as fluctuations in weight, restlessness, or changes in blood pressure.

It’s crucial to take your dose of levothyroxine when its intestinal absorption won’t be impaired by digestion, says Ani Shenian, Pharm.D., a clinical pharmacist in Los Angeles. According to Dr. Shenian, that means avoiding the following foods that make levothyroxine less effective within three to four hours of your dose, including:

• High-fiber foods (such as sweet potatoes, black beans, and avocado)
• Caffeinated drinks (such as coffee)
• Foods or beverages that contain calcium (such as milk and other dairy products)
• Iron-rich foods
• Grapefruit and grapefruit juice
• Soy-based flour (such as that used in infant formula)
• Cottonseed flour
• Walnuts

To ensure optimal absorption of levothyroxine, take it at least three to four hours after your last meal.

Drug interactions

Tell your healthcare provider and pharmacist about all medications you are taking, as it could impact when you take your levothyroxine dosage. There are several prescription medications and over-the-counter supplements that interact with levothyroxine, including:

• Antacids
• Calcium supplements
• Iron supplements
• Proton pump inhibitors such as Nexium (esomeprazole), Prevacid (lansoprazole), and Prilosec (omeprazole)
• Simethicone
• Salicylate pain relievers such as aspirin and aspirin-containing products, choline magnesium trisalicylate, Dolobid (diflunisal), and magnesium salicylate
• Niacin
• Nonsteroidal anti-inflammatory medications (NSAIDs) such as Advil, Motrin (ibuprofen), or Aleve (naproxen)
• Prevalite (cholestyramine)
• Welchol (colesevelam)
• Colestid (colestipol)
• Renvela, Renagel (sevelamer)
• Kayexalate (sodium polystyrene sulfonate)

You should space your levothyroxine dosage out with any of these pills by at least four hours.

3. Stay consistent

Whether you take levothyroxine in the morning or at night, make sure to take it at the same time each day to maintain stable thyroid hormone levels. “Consistency is key, regardless of the timing,” says Dr. Langdon.

The bottom line

Taking levothyroxine at night can be a convenient alternative for patients who find morning doses difficult to manage. Provided it’s taken on an empty stomach, it can offer similar benefits to morning dosing, with no significant effect on thyroid function or quality of life. As long as you monitor your side effects and stay in communication with your healthcare provider, taking levothyroxine at night can be just as effective as taking it in the morning.