Can I take 50 and Vitamin b3 together?
Drug interaction guide
Originally published 14 Mar 2026
Meets Patient’s editorial guidelines
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Taking 5-HTP (5-hydroxytryptophan) and Vitamin B3 (Niacin) together can lead to an increase in serotonin levels in the body. While both are often used to support mood, taking them at the same time might cause your serotonin levels to become too high. This can lead to side effects like feeling jittery, a racing heart, or nausea. Additionally, Vitamin B3 can sometimes cause 'flushing' (red, itchy, or hot skin), and 5-HTP may make some people feel more sensitive to these side effects.
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Why this happens
The body uses Vitamin B3 as part of the process to convert the amino acid tryptophan into serotonin. 5-HTP is the direct precursor to serotonin. By taking both, you are providing the body with the raw materials (5-HTP) and the chemical 'tools' (B3) to produce serotonin more rapidly. This creates an additive effect on serotonin production.
What you should do
Back to contentsIt is best to use caution when combining these two supplements. If you decide to take both, start with low doses and monitor how you feel. If you experience a rapid heartbeat, shivering, heavy sweating, or significant agitation, stop taking them and speak to a healthcare professional. Always inform your doctor or pharmacist before starting new supplements, especially if you are already taking prescribed antidepressants.
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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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Can I take Acetaminophen and Levocetirizine together?
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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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