git add

Skip to main content

Can I take Amitriptyline and Thyroxine together?

Drug interaction guide

Taking amitriptyline and thyroxine (levothyroxine) together may increase the risk of heart-related side effects, such as a fast heartbeat or an irregular heart rhythm (palpitations). It may also increase the risk of feeling anxious or shaky.

Video picks for Drug interactions

Continue reading below

Why this happens

Thyroxine makes the heart more sensitive to certain chemicals in the body, such as adrenaline. Amitriptyline increases the levels of these chemicals. When used together, they can have an 'additive' effect, putting extra strain on the heart and nervous system.

This combination is commonly prescribed, but you should be monitored by your doctor. If you notice a very fast heartbeat, chest pain, or severe tremors, contact your GP. Do not stop taking either medication without medical advice.

Continue reading below

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.

Continue reading below

Article history

The information on this page is written and peer reviewed by qualified clinicians.

  • 12 May 2026 | Originally published
flu eligibility checker

Ask, share, connect.

Browse discussions, ask questions, and share experiences across hundreds of health topics.

symptom checker

Feeling unwell?

Assess your symptoms online for free

Sign up to the Patient newsletter

Your weekly dose of clear, trustworthy health advice - written to help you feel informed, confident and in control.

Please enter a valid email address

By subscribing you accept our Privacy Policy. You can unsubscribe at any time. We never sell your data.