Can I take Lactulose and Oxypro together?
Drug interaction guide
Originally published 25 Jan 2026
Meets Patient’s editorial guidelines
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Oxypro (oxycodone) is an opioid painkiller that commonly causes constipation as a side effect. Lactulose is a laxative used to treat this constipation. While they are often prescribed together for this reason, the oxycodone is essentially 'fighting' against the laxative, which may make the lactulose less effective than usual.
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Why this happens
Oxypro (oxycodone) slows down the movement of the digestive system (gut motility). Lactulose works by drawing water into the bowel to soften stools and stimulate movement. These two medications have opposing effects on the speed of your digestive tract.
What you should do
Back to contentsIt is safe and very common to take these together, but you should monitor your bowel habits. If you remain constipated despite taking lactulose, speak to your doctor or pharmacist, as you may need a different type of laxative (such as a stimulant laxative) to counteract the effects of the Oxypro. Ensure you drink plenty of water.
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Using other medicines
Back to contentsTaking 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.
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Article history
The information on this page is written and peer reviewed by qualified clinicians.
25 Jan 2026 | Originally published
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