Can I take 50 and Light therapy together?
Drug interaction guide
Originally published 14 Mar 2026
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Taking 5-HTP while using light therapy (phototherapy) may increase your risk of developing 'Serotonin Syndrome'. This is a rare but serious condition caused by having too much serotonin in your body. Symptoms can include feeling very agitated, confused, sweaty, or having a fast heartbeat and muscle twitching. Additionally, 5-HTP can make your skin and eyes more sensitive to light, which could lead to rashes or eye discomfort during light therapy sessions.
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Why this happens
Both 5-HTP and light therapy work by increasing the levels of serotonin (a chemical messenger) in your brain. When used together, they can raise serotonin to unsafe levels. Furthermore, some supplements that affect serotonin can cause 'photosensitivity', making your body more reactive to the bright light used in therapy.
What you should do
Back to contentsYou should speak to your doctor or a pharmacist before using these two treatments together. If you decide to use both, start with a very low dose of 5-HTP and monitor yourself closely for any unusual symptoms. Always wear the protective eyewear provided during light therapy. If you feel unusually agitated, hot, or notice your heart racing, stop both treatments and seek medical advice immediately.
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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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