Can I take 20 and Janumet together?
Drug interaction guide
Originally published 14 Mar 2026
Meets Patient’s editorial guidelines
- DownloadDownload
- Share
- Language
- Discussion
- Audio Version
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.
In this article:
Continue reading below
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.
What you should do
Back to contentsIt 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.
Continue reading below
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.
Patient picks for Drug interactions

Treatment and medication
Can I take Abrysvo powder and Inhalation powder. together?
There is no known direct interaction between the Abrysvo vaccine and inhaled medicines (inhalation powders). However, if you are unwell or have a fever, you may need to delay your vaccination.

Treatment and medication
Can I take 150 and Zigduo together?
Taking aspirin (75mg to 150mg) with Xigduo (which contains dapagliflozin and metformin) can increase the risk of your blood sugar dropping too low (hypoglycaemia). It may also increase the risk of a rare but serious condition called lactic acidosis, where too much acid builds up in your blood.
Article history
The information on this page is written and peer reviewed by qualified clinicians.
14 Mar 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.