Can I take Lanzoprole and Metformin together?
Drug interaction guide
Originally published 25 Jan 2026
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Taking lansoprazole and metformin together is generally safe, but lansoprazole may slightly increase the amount of metformin in your blood. This could potentially increase the risk of side effects like an upset stomach or, in very rare cases, a more serious condition called lactic acidosis. Additionally, long-term use of lansoprazole can lower your Vitamin B12 levels, which is a known side effect of metformin as well.
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Why this happens
Lansoprazole may slightly interfere with how metformin is cleared from the body by the kidneys. Furthermore, both drugs can reduce the absorption of Vitamin B12 from your diet through different methods in the digestive tract.
What you should do
You can take these medicines together. However, you should monitor for any new or worsening side effects, such as nausea, diarrhoea, or stomach pain. If you take both long-term, ask your doctor to check your Vitamin B12 levels during your routine blood tests.
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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.
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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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