Can you take Synthroid at night?

Synthroid (levothyroxine sodium) is a prescription drug that works as a synthetic thyroid hormone replacement. It is typically prescribed to people with hypothyroidism (underactive thyroid), a condition where the thyroid does not produce enough hormones naturally. This medication helps replenish and balance thyroid hormone levels in the body, which are necessary for metabolism, energy levels, and overall health. 

If you just started taking Synthroid or you’ve been taking it for a while, you might be wondering about its dosing schedule, particularly whether taking it at night is an option. The straightforward answer is that patients may take Synthroid at night as long as it’s on an empty stomach to improve its absorption. Whether you take it at night or in the morning, it is important to take Synthroid at the same time each day to keep hormone levels stable. 

Continue reading to learn more about whether Synthroid can be taken at night and what the potential effects are. 

How is Synthroid normally taken?

Synthroid is an oral brand-name drug containing the active ingredient levothyroxine sodium. It is approved by the Food and Drug Administration (FDA) to help with conditions like an underactive thyroid and, in some cases, thyroid cancer. Knowing how to take it correctly can make a difference in getting the most benefit from treatment.

Synthroid is a tablet available in various doses, from 25 to 300 micrograms (mcg). The specific dosage is tailored to an individual’s needs based on symptoms of hypothyroidism and current thyroid hormone levels, which are typically measured by thyroid-stimulating hormone (TSH) tests. High TSH levels typically indicate an underactive thyroid gland, while low TSH levels suggest an overactive thyroid.

Synthroid dosage is also calculated based on a person’s body weight and age. The dosage may also vary based on other health conditions, including heart disease and heart failure. A healthcare provider may also take into account other medications you take, as Synthroid can interact with various medications that can affect its blood levels or increase the risk of side effects. 

It is key to follow the prescribed dosage closely, especially for certain groups of patients, like children who might need crushed tablets mixed with water for easier administration. Altering the timing of Synthroid without consulting a healthcare professional can lead to changes in thyroid levels and potentially affect overall health.

Recommended time for taking Synthroid

According to the FDA drug label, Synthroid is typically taken in the morning on an empty stomach, usually 30 minutes to an hour before breakfast. For maximum absorption of levothyroxine, it’s advised to take the tablet with a full glass of water. 

Synthroid may require careful timing to maximize its effectiveness. While it’s generally recommended to be taken in the morning, the dosage can vary depending on an individual’s health condition. It may also depend on their schedule and when they find it most convenient to take their medications.

Can you take Synthroid at night?

Taking Synthroid at night may be equally effective as taking it in the morning, as long as it is done correctly. The main concern is that it should be consumed on an empty stomach to maximize absorption. Some people prefer to take Synthroid at bedtime, at least three to four hours after their last meal.

Studies have shown mixed results in regard to the timing of levothyroxine for managing thyroid health. One study suggests taking it at least two hours after dinner in the evening keeps thyroid hormone levels steady or improves them compared to morning doses. However, another study indicates that taking it at least an hour before breakfast is more effective than evening doses.

Many people may find that it’s more convenient and easier to take Synthroid regularly if it’s taken in the evening. For example, people with inconsistent schedules or work shifts might find a nighttime dose more manageable. 

What happens if you take Synthroid at night?

Insomnia or trouble sleeping is a known potential side effect of Synthroid. Therefore, if you take it too close to bedtime, you might find it difficult to get a good night’s rest. For some people, taking Synthroid may come with other side effects that could interfere with sleep, including headache, shortness of breath, nervousness, irritability, and tremors. In addition, Synthroid may cause increased heart rate, skin rash, and heat intolerance. 

It’s important to remember that higher doses of Synthroid typically carry a higher risk of side effects that can interfere with sleep. Since Synthroid is commonly prescribed to address symptoms of hypothyroidism like fatigue or low energy, balancing thyroid hormone levels with this medication should ideally alleviate these issues without causing insomnia.

In fact, some people report improved sleep and quality of life with nighttime dosing. A switch to nighttime dosing should always be personalized, with individual circumstances and health conditions in mind.

How to switch from morning to nighttime dosing

When transitioning from taking Synthroid in the morning to night time, it is key to do so properly to ensure the medication is effective and minimize potential side effects. Below are guidelines to follow:

• Consult with your healthcare provider. Make an appointment to discuss the changes you’re considering. Your healthcare provider will provide personalized advice and may adjust your dosing schedule based on your specific health needs.
• Take note of the timing of the medication. If you usually take Synthroid in the morning, your healthcare provider will typically recommend waiting until the next night to take your next dose if you’re switching to an evening dose. Taking Synthroid within the same day could lead to increased blood levels of Synthroid and increased side effects. After switching, begin taking your dose at the same time each night.

• Watch the timing of when you last ate. Synthroid should be taken on an empty stomach for optimal absorption. If you’re going to eat in the evening before taking Synthroid, wait at least three hours after eating before taking the medication.

If you’re considering switching the time you take Synthroid, it’s important to follow these steps with guidance from your healthcare provider. 

Other considerations when taking Synthroid at nighttime

When taking Synthroid at night, you may want to be aware of potential interactions that may affect its effectiveness. Specific medications can hinder the absorption of Synthroid, potentially altering thyroid hormone levels.

Drug interactions

Taking Synthroid with certain medications may need to be avoided or done with caution. It’s recommended to take Synthroid at least four hours before or after medications that can affect its absorption, such as:

• Proton pump inhibitors (PPIs): Commonly used to treat conditions like acid reflux, PPIs can decrease the absorption of Synthroid. If someone is on PPIs, they might need to take Synthroid at a different time to prevent effects on absorption.
• Antacids: They may interfere with Synthroid absorption if they contain aluminum or magnesium.
• Phosphate binders: These are often prescribed to patients with kidney disease to control phosphorus levels. They can bind to Synthroid in the gastrointestinal tract, which may lead to decreased thyroid hormone absorption. 
• Bile acid sequestrants: These medications are used to lower cholesterol and can also prevent Synthroid from being properly absorbed. Taking Synthroid several hours before or after bile acid sequestrants can help manage this interaction.

This is not a complete list of drugs that can interact with Synthroid. Always tell your healthcare provider about all medications you take before starting Synthroid. 

Food interactions

When taking Synthroid in the evening, certain foods might interact with the medication and affect how it works. The following foods can affect the absorption of Synthroid, potentially altering its effectiveness:

• High-fiber foods: These include items such as sweet potatoes, black beans, and avocados. High-fiber foods can slow the absorption of Synthroid.
• Soy and cottonseed meal: Both can make Synthroid less effective.
• Walnuts: These nuts can affect how well your body absorbs the medication.

• Dairy and calcium-fortified juices: Dairy products should be consumed several hours before or after taking Synthroid due to the presence of calcium.
• Grapefruit juice: Although not always mentioned, grapefruit juice may interfere with the effectiveness of various medications, including Synthroid.

• Coffee: Having coffee too close to the time you take Synthroid can slow drug absorption. It’s recommended to wait at least an hour after taking your medication before having coffee.

Coordinate with your healthcare provider to adjust the timing of your medications if needed. That way, you can ensure you’re getting the most benefit from Synthroid. 

Importance of blood test monitoring

Be sure to follow your healthcare provider’s recommendations for blood test monitoring to ensure your thyroid hormone levels are normal. It’s important to check your thyroid function regularly, typically every few weeks to months, especially after any changes in your routine.  

By monitoring these levels regularly, you can see if taking medication at night or in the morning significantly affects how well it works. These tests help healthcare providers understand whether taking the medication at night keeps your thyroid hormone levels where they should be.

Working with your healthcare provider can help optimize the timing and effectiveness of your medications without serious side effects.

Bottom line

Synthroid’s FDA label recommends taking it in the morning at least 30 minutes to an hour before breakfast. However, for some individuals, taking Synthroid at night can be effective, particularly if it is done consistently and on an empty stomach. Certain foods and medications may interfere with the absorption of Synthroid. Therefore, it’s always a good idea to consult a healthcare provider on the appropriate dosage and timing of administration.