Can I take Lercanidipine and Levothyroxine together?

Why this happens

Lercanidipine is a calcium channel blocker used for high blood pressure, and levothyroxine is a hormone replacement for an underactive thyroid. They do not interfere with each other's absorption or metabolism. However, thyroid hormones naturally affect heart rate and blood pressure; therefore, changes in your thyroid dose might indirectly change how much blood pressure medicine you need.

What you should do

You can take these two medicines together. It is usually best to take levothyroxine on an empty stomach first thing in the morning (30-60 minutes before breakfast) and lercanidipine at least 15 minutes before a meal. Continue to have your regular blood tests to monitor your thyroid levels and your routine blood pressure checks.

Important precautions

Severe liver or kidney disease

Lercanidipine is not recommended if you have severe liver or kidney problems. Ensure your doctor is aware of your condition before starting treatment.

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 lercanidipine. Alcohol can increase the blood-pressure-lowering effect of the medicine, which may make you feel dizzy, lightheaded, or faint.

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.

Grapefruit and grapefruit juice

You must not eat grapefruit or drink grapefruit juice while taking lercanidipine. Grapefruit can significantly increase the amount of the medicine in your blood, making side effects like dizziness, headaches, and a fast heartbeat much more likely.

High-fat meals

Lercanidipine should be taken at least 15 minutes before a meal. Taking it with or immediately after a high-fat meal can significantly increase the amount of medicine absorbed by your body, which may lead to more side effects.

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.

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.

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.

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.