Can I take Levothyroxine and Coffee together?

You should avoid taking levothyroxine and coffee at the same time as coffee can significantly reduce the amount of medicine your body absorbs.

Why this happens

Levothyroxine is a sensitive medicine that needs a very specific environment in the stomach to be absorbed properly. Coffee contains compounds that can bind to the medicine or change how quickly it moves through your digestive system, preventing it from entering your bloodstream effectively.

How to know if you're having a drug interaction

You may be experiencing an interaction between levothyroxine and coffee if you notice:

• Your thyroid symptoms aren’t improving (e.g., fatigue, weight changes, feeling cold).

• Unexplained changes in energy or mood.

• Lab tests showing lower-than-expected thyroid hormone levels.

Coffee can reduce the absorption of levothyroxine if taken too close together, making the medication less effective.

What you should do

If you experience these side effects, you should:

• Take levothyroxine on an empty stomach with water and wait at least 30–60 minutes before drinking coffee or other beverages.

• Do not change your dose on your own-talk to your doctor if your symptoms continue.

• Schedule a follow-up blood test if your thyroid levels seem off.

• Keep a consistent routine for taking your medication each day to ensure it works properly.

This helps your body absorb the medication effectively and keeps your thyroid levels stable.

Important precautions

Coffee consumption timing

You must wait at least 30 to 60 minutes after taking levothyroxine before drinking coffee. Coffee significantly reduces the absorption of the medicine, which can lead to unstable thyroid levels.

Heart conditions (e.g. angina, heart failure)

If you have a heart condition, your dose must be started very low and increased slowly. Contact your doctor immediately if you experience chest pain or palpitations, as levothyroxine increases the workload on your heart.

Interaction with supplements (Calcium/Iron)

Do not take calcium tablets, iron supplements, or multivitamins at the same time as levothyroxine. You must leave a gap of at least 4 hours between these supplements and your levothyroxine to ensure the medicine works.

Diabetes

Levothyroxine can raise blood sugar levels. If you have diabetes, you must monitor your blood glucose more closely when starting or changing your dose, as your diabetes medication may need to be increased.

Food and drink warnings

Alcohol

It is best to avoid or strictly limit alcohol while taking levothyroxine. While there is no direct chemical reaction, alcohol can affect thyroid function and may worsen symptoms like tiredness or mood changes.

It is best to avoid or strictly limit alcohol when consuming caffeine. Caffeine can mask the sedative effects of alcohol, making you feel more alert than you actually are. This can lead to 'wide-awake drunkenness', increasing the risk of alcohol-related accidents or overconsumption.

Timing of dose and food/drink

Take your levothyroxine on an empty stomach, at least 30 to 60 minutes before breakfast or any caffeine. Food, milk, and coffee prevent the medicine from being absorbed properly.

Dairy products (Milk, Yoghurt, Cheese)

Avoid consuming dairy products at the same time as your levothyroxine. Calcium found in dairy can interfere with how your body absorbs the medicine, making it less effective. It is best to wait at least 4 hours between taking levothyroxine and consuming dairy.

Soya products

Soya can interfere with the absorption of levothyroxine. If you regularly eat or drink soya products, your doctor may need to monitor your thyroid levels more closely. Avoid consuming soya at the same time as your dose.

Kelp and Seaweed

These foods are naturally high in iodine. Too much iodine can interfere with your thyroid treatment and make your condition worse.

High-fibre foods

A diet very high in fibre can reduce the absorption of levothyroxine. If you significantly change your fibre intake, inform your doctor as your dose may need adjusting.

Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.

Disclaimer

This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.