Swanson L-Tryptophan is a dietary supplement that supports balanced serotonin production and promotes restful sleep, helping you feel calmer and sleep soundly.

Available Sizes & Variants:

60 capsules - standard daily dose for ongoing support.

Benefits & Features:

• Supports mood balance with a calming effect to help you feel steadier.
• Promotes restful sleep.
• The star ingredient, L-tryptophan, acts as a serotonin and melatonin precursor to support sleep quality.
• Designed for daily use alongside a vitamin d supplement and protein shakes.
• Quality is backed by Ajipure/TryptoPure pharmaceutical grade L-tryptophan, with rigorous batch testing to ensure consistency and safety, and it can be used with n acetylcysteine as part of wellness routine.

Swanson L-Tryptophan draws on decades of wellness know-how, delivering pharmaceutical-grade L-tryptophan from Ajipure/TryptoPure. The brand commitment to transparency means strict batch testing and quality checks on every lot, helping you trust the product you take nightly. Sourced as part of Ajinomoto's high-purity supply chain, this supplement fits naturally into a broader sleep and mood routine. It works well with a vitamin d supplement and protein shakes, supporting a calm, rested start to your day.

L-tryptophan, capsule shell: gelatin, brown rice flour, anti-caking agents: magnesium salts of fatty acids and silicon dioxide.

• GTIN: 87614115023
• Manufacturer: Swanson
• Categories: SwansonTryptophan
• Best buy: 6 - 24 months+

United Kingdom Shipping:

Orders placed by 2pm (Monday to Friday) are dispatched the same day. Orders placed after 2pm will be dispatched the next working day.

Free shipping on orders over £50 to the UK.

Returns: Our products are meant to make you feel healthy and at your best. If you need to return your item, you can do so free of charge within 30 days in the same original and unopened packaging. Subject to T&C's.

Take one capsule of Swanson L-Tryptophan, 500mg, with plenty of water 30-60 minutes before bedtime for optimal results. Store in a cool, dry place out of reach of children and away from direct sunlight. Consult a doctor before use if you are pregnant, nursing, or have a medical condition. Do not exceed the recommended daily intake.

Please consult the product packaging for accurate instructions on how to use the product.

The Active Ingredient Is: L-Tryptophan

L-Tryptophan is an essential amino acid that your body uses to make serotonin and melatonin, compounds involved in mood control and sleep cycles. This form is pharmaceutical-grade L-tryptophan supplied from Ajipure or TryptoPure, a well recognised source of high-purity tryptophan.

In this product, the ingredient comes as L-Tryptophan suitable for dietary supplementation, the body cannot synthesize this amino acid and thus relies on dietary intake to support normal biological processes.

What Does L-Tryptophan Do?

L-Tryptophan is a precursor to serotonin and melatonin, helping with normal neurotransmitter function and sleep-related processes. This ties in with the nutrient’s role in supporting regular sleep and mood-related functions through its metabolic connections.

It’s used to support normal physiological processes associated with sleep and relaxation without providing dosage instructions in this section.

*This product is not intended to diagnose, treat, cure, or prevent any disease.

Swanson has a long standing track record as a trusted US supplement brand, recognised for sourcing pharmaceutical‑grade L‑tryptophan from Ajinomoto and putting batches through extensive testing. This heritage and commitment to supply chain integrity underpins our confidence in Swanson as a dependable long‑term partner for Welzo customers. The product uses carefully sourced L‑tryptophan from TryptoPure®/Ajipure®, helping ensure purity and consistency across batches, with rigorous batch testing highlighted by the brand’s formulation claims. This focus on high‑quality ingredients aligns with our emphasis on safety, traceability and clear quality standards.

Swanson L‑Tryptophan is therefore a strong fit for our sleep and mood support category, and it aligns with our commitment to evidence‑based selection. Our recommendation is grounded in Swanson’s proven manufacturing discipline and our internal evaluation process, including consideration of how the brand’s quality controls translate to a reliable consumer experience. This brand was evaluated by our expert team of doctors, nurses, and nutritionists for compliance with the certifications we require, and their UK regulatory familiarity supports safe local market access.