Can I take Calcium and Doxycycline together?
Drug interaction guide
Originally published 25 Jan 2026
Meets Patient’s editorial guidelines
- DownloadDownload
- Share
- Language
- Discussion
Taking calcium at the same time as doxycycline can stop the antibiotic from working properly. The calcium attaches to the medicine in your stomach, which prevents your body from absorbing it into your bloodstream. This means the infection you are treating might not clear up as it should.
In this article:
Continue reading below
Why this happens
This is an absorption issue called 'chelation'. Calcium binds to the doxycycline molecules in the digestive tract to form a large complex that the body cannot absorb.
What you should do
Back to contentsYou should separate the doses of these two substances. Take your doxycycline at least 2 hours before or 3 hours after consuming calcium-rich foods (like milk, cheese, or yoghurt) or calcium supplements.
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 Amitriptyline and Lactulose together?
Amitriptyline can cause constipation as a side effect. This may make lactulose (a laxative) less effective or mean you need a higher dose to see results.
Treatment and medication
Can I take Amitriptyline and Gabapentin together?
Taking amitriptyline and gabapentin together can make you feel very sleepy, dizzy, or confused. It can also make it harder to concentrate and may slow down your breathing or affect your coordination, increasing the risk of falls.
Article history
The information on this page is written and peer reviewed by qualified clinicians.
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.