Skip to main content

Can I take 100 and Sulfasalazine together?

Drug interaction guide

Taking aspirin and sulfasalazine together can increase the amount of sulfasalazine in your blood. This may increase your risk of experiencing side effects such as nausea, stomach upset, or headaches. Additionally, both medicines can be harsh on the stomach lining, which may increase the risk of stomach irritation or ulcers.

Video picks for Drug interactions

Continue reading below

Why this happens

Both aspirin and sulfasalazine belong to a family of medicines called salicylates. Because they are chemically similar, taking them together can lead to a 'double dose' effect. Aspirin can also compete with sulfasalazine for clearance from the body, leading to higher levels of the medicine in your system.

You should speak to your doctor before taking these two medicines together. They may want to monitor you more closely for side effects or adjust your dosage. If you experience any unusual stomach pain, indigestion, or dark/tarry stools, contact your doctor immediately.

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.