Skip to main content

Can I take 90 and Ferrous together?

Drug interaction guide

Taking these two together can significantly reduce the amount of iron your body absorbs. This means the iron supplement may not work effectively to treat or prevent iron deficiency (anaemia).

Video picks for Drug interactions

Continue reading below

Why this happens

Aspirin (the active ingredient in '90' or Aspirin 90mg) can cause tiny amounts of irritation or bleeding in the stomach lining. More importantly, when taken at the same time, certain components can bind together in the gut, or the aspirin can affect the stomach acid levels required for the iron (ferrous) to dissolve and be absorbed into your bloodstream.

To ensure you get the full benefit of your iron supplement, space the doses apart. Take your iron supplement at least 2 hours before or 2 hours after taking your aspirin. If you notice black, tarry stools or persistent stomach pain, speak to your doctor.

Continue reading below

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.

Continue reading below

Article history

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

  • 14 Mar 2026 | Originally published
flu eligibility checker

Ask, share, connect.

Browse discussions, ask questions, and share experiences across hundreds of health topics.

symptom checker

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.

Please enter a valid email address

By subscribing you accept our Privacy Policy. You can unsubscribe at any time. We never sell your data.