Skip to main content

Can I take Amitriptyline and Oxypro together?

Drug interaction guide

Taking amitriptyline and Oxypro (oxycodone) together can cause extreme sleepiness, dizziness, and severe breathing difficulties. It may also lead to a rare but serious condition called serotonin syndrome, which can cause confusion, sweating, and muscle twitching.

Continue reading below

Why this happens

Both drugs slow down the central nervous system (brain and spinal cord). Amitriptyline also increases serotonin levels, which can be further affected by oxycodone, leading to a dangerous build-up. Additionally, amitriptyline can slow down the body's ability to process oxycodone, making its effects stronger and longer-lasting.

You must speak to your doctor before taking these medicines together. If your doctor prescribes both, they will likely start you on the lowest possible doses. Seek immediate medical help if you feel unusually sleepy, have trouble breathing, or feel very confused.

Continue reading below

Suicidal thoughts and mood changes

Amitriptyline can increase the risk of suicidal thoughts or self-harm, particularly when first starting treatment or changing doses. Seek immediate medical help if your mood changes or you feel depressed.

Respiratory Depression / Breathing Problems

Both medicines can slow your breathing. Taking them together significantly increases the risk of dangerous, shallow breathing or stopping breathing altogether. Seek emergency help if you feel extremely drowsy or have difficulty breathing.

Opioid Addiction and Dependence

Oxypro is an opioid that carries a high risk of addiction and physical dependence, even at prescribed doses. Long-term use can lead to withdrawal symptoms if stopped suddenly.

Heart Rhythm Disorders

Amitriptyline can affect your heart rhythm (QT prolongation). It must be used with extreme caution if you have an existing heart condition or a history of heart attacks.

Alcohol

You must avoid or strictly limit alcohol while taking these medicines. Both amitriptyline and Oxypro cause drowsiness and slow your breathing; alcohol significantly increases these effects, which can lead to dangerous levels of sedation, coordination loss, and respiratory depression.

Grapefruit juice

Avoid drinking grapefruit juice or eating grapefruit. It can increase the amount of oxycodone in your blood to potentially toxic levels, increasing the risk of serious side effects like extreme sleepiness or breathing difficulties.

Caffeine (Coffee, tea, energy drinks)

Amitriptyline can sometimes cause a fast or irregular heartbeat. High intake of caffeine may worsen these heart-related side effects or increase feelings of restlessness and anxiety.

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.

  • 25 Jan 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.