Can I take Oxycodone and Quinine together?
Drug interaction guide
Originally published 25 Jan 2026
Meets Patient’s editorial guidelines
- DownloadDownload
- Share
- Language
- Discussion
- Audio Version
- Add to preferred sources on Google
Taking quinine with oxycodone can increase the amount of oxycodone in your blood. This makes the side effects of the painkiller much stronger and more dangerous. You may experience extreme sleepiness, dizziness, confusion, and, most seriously, shallow or slow breathing. There is also a risk of an irregular heartbeat (heart palpitations).
Why this happens
Quinine can interfere with the way your liver breaks down oxycodone (the active ingredient in Oxypro), leading to a buildup of the painkiller in your system. Additionally, both drugs have the potential to affect the electrical activity of your heart (prolonging the QT interval), and using them together increases this risk.
What you should do
You should speak to your doctor before taking these two medicines together. If your doctor confirms you must take both, they may need to lower your dose of oxycodone. Seek medical help immediately if you feel unusually sleepy, have trouble breathing, or feel your heart racing or skipping a beat. Avoid driving or operating machinery while taking this combination.
Important precautions
Opioid dependence/Addiction
Oxycodone is highly addictive. Long-term use can lead to physical dependence and withdrawal symptoms if stopped suddenly.
Respiratory depression
Oxycodone can dangerously slow or stop your breathing, especially when first starting or if the dose is increased. This risk is much higher if taken with alcohol or other sedatives.
Heart rhythm disorders (e.g. Long QT syndrome)
Quinine can cause serious, potentially fatal heart rhythm changes; avoid if you have a history of heart rhythm problems.
Blood disorders (e.g. Thrombocytopenia)
Quinine can cause a sudden, severe drop in platelets which can lead to life-threatening bleeding; stop immediately if you notice unexplained bruising or bleeding.
Tinnitus (ringing in the ears) or hearing loss
Quinine can cause permanent hearing damage or worsen existing tinnitus. Stop taking the medicine immediately if you notice any changes to your hearing or ringing in your ears.
Food and drink warnings
Alcohol
It is best to avoid or strictly limit alcohol when taking oxycodone. Combining alcohol with this medicine significantly increases the risk of dangerous side effects, such as severe drowsiness, breathing difficulties, and a potentially fatal overdose.
It is best to avoid or strictly limit alcohol while taking quinine. Both alcohol and quinine can affect your heart rhythm and cause dizziness; combining them may increase these risks.
Grapefruit juice
Avoid drinking grapefruit juice or eating grapefruit. Grapefruit can increase the levels of these medicines in your blood, making side effects more likely and potentially more severe.
Tonic water
Be aware that tonic water contains small amounts of quinine. While usually safe in small amounts, consuming large quantities of tonic water alongside quinine tablets could increase the risk of side effects like ringing in the ears or blurred vision.
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.
Patient picks for Drug interactions

Drug interactions checker
Can I take Metformin and Ibuprofen together?
Taking ibuprofen while on metformin can increase the risk of kidney problems and a rare but serious condition called lactic acidosis. Ibuprofen can also make metformin stay in your body longer, potentially increasing its side effects.

Drug interactions checker
Can I take Lisinopril and Potassium together?
Taking lisinopril and potassium supplements together can cause the levels of potassium in your blood to become dangerously high (a condition called hyperkalaemia). While your body needs potassium for your heart and muscles to work, too much of it can lead to serious heart rhythm problems or even cause the heart to stop. Symptoms of high potassium can include muscle weakness, tingling sensations, or palpitations, but often there are no symptoms until the level is very high.
Article history
The information on this page is written and peer reviewed by qualified clinicians.
Article also available in English, German, Spanish, French, Italian, Portuguese, Hindi, Hebrew, Arabic, and Swedish.
25 Jan 2026 | Originally published

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

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.
By subscribing you accept our Privacy Policy. You can unsubscribe at any time. We never sell your data.
More in drug interactions checker
- Can I take Adcal-D3 and Carbocisteine together?
- Can I take Allopurinol and Co-amoxiclav together?
- Can I take Alogliptin and Fibre supplements together?
- Can I take Amitriptyline and Ramipril together?
- Can I take Amlodipine and Empagliflozin together?
- Can I take Aspirin and Doxazosin together?
- Can I take Atorvastatin and Pyridostigmine together?
- Can I take Bactrim and Venlafaxine together?
- Can I take Candesartan and Mirtazapine together?
- Can I take Clarithromycin and Sertraline together?
- Can I take Cordyceps and Maitake together?
- Can I take Cordyceps and Reishi together?
- Can I take Furosemide and Strivit D3 together?
- Can I take Glibenclamide and Empagliflozin together?
- Can I take Glucosamine and Oestrogel pump-pack together?
- Can I take Ibuprofen and Diclofenac together?
- Can I take Lion's mane and Turkey tail together?
- Can I take Naproxen and Sertraline together?
- Can I take Sedoxil and Vitamin D together?
- Can I take Spironolactone and Potassium together?