Can I take 50 and Methenamine hippurate together?
Drug interaction guide
Originally published 14 Mar 2026
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Taking 5-HTP (5-hydroxytryptophan) with methenamine hippurate may make the methenamine less effective at treating or preventing urinary tract infections (UTIs).
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Why this happens
Methenamine hippurate needs acidic urine (a low pH) to turn into formaldehyde, which is the substance that kills bacteria in the bladder. 5-HTP can sometimes make the urine more alkaline (less acidic), which prevents the methenamine from working properly.
What you should do
Back to contentsIt is best to avoid taking 5-HTP while you are using methenamine hippurate. If you must take both, speak with your doctor or pharmacist. They may suggest monitoring your urine acidity using dipsticks or adjusting your diet to ensure your urine stays acidic enough for the medicine to work.
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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.
14 Mar 2026 | Originally published

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