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Can I take 20 and Janumet together?

Drug interaction guide

Combining alcohol with Janumet (which contains metformin and sitagliptin) can lead to dangerously low blood sugar levels (hypoglycaemia). It also significantly increases the risk of a rare but very serious condition called lactic acidosis, where too much acid builds up in your blood. Additionally, alcohol can worsen the risk of inflammation of the pancreas (pancreatitis), which is a potential side effect of sitagliptin.

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Why this happens

Alcohol interferes with the liver's ability to release glucose into the bloodstream, making low blood sugar more likely. Both alcohol and the metformin in Janumet increase the production of lactate; if the body cannot clear this quickly enough, it leads to lactic acidosis. Both substances can also irritate the pancreas.

It is best to avoid alcohol entirely while taking Janumet. If you do choose to drink, you must strictly limit your intake, never drink on an empty stomach, and monitor your blood sugar levels very closely. Seek immediate medical help if you experience signs of lactic acidosis, such as extreme tiredness, muscle pain, breathing difficulties, or severe stomach pain.

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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.

Article history

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

  • 14 Mar 2026 | Originally published
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