Can I take 50 and Certirizine together?
Drug interaction guide
Originally published 12 May 2026
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Taking 5-HTP and cetirizine together may increase the risk of side effects such as drowsiness, dizziness, and difficulty concentrating. You may feel more 'spaced out' or sleepy than usual.
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Why this happens
Both substances can affect the central nervous system. While cetirizine is a 'non-drowsy' antihistamine, it can still cause mild sedation in some people. 5-HTP increases serotonin levels, which can also have a calming or sedative effect. When used together, these effects can add up.
What you should do
Back to contentsUse caution when combining these two. It is best to see how you react to the combination before driving or operating machinery. If you feel excessively sleepy or dizzy, you should stop taking the 5-HTP and speak with your pharmacist or doctor.
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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.
12 May 2026 | Originally published

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