Can I take Fibre supplements and Losartin together?
Drug interaction guide
Originally published 25 Jan 2026
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Taking fibre supplements at the same time as losartan may reduce the amount of medicine your body absorbs. This could make your blood pressure medication less effective, potentially leading to higher blood pressure readings than expected.
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Why this happens
Fibre supplements (like psyllium husk or methylcellulose) can act like a sponge in your digestive system. They can bind to the losartan molecules or create a physical barrier that prevents the medicine from passing through the gut wall into your bloodstream.
What you should do
Back to contentsYou do not need to stop taking either, but you should space them out. Take your losartan at least 2 hours before or 4 hours after taking your fibre supplement. Consistency is key—try to take them at the same times each day and monitor your blood pressure regularly.
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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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