L-Tryptophan
Amino Acid
Also known as: TRP, Tryptophan
B
Grade B๐ 500-2000 mg daily๐ฏ 3 primary uses๐ 2 synergiesโ ๏ธ Review warnings
Levels upMovement+50 pts
Overview
Essential amino acid precursor to serotonin and melatonin. Supports mood and sleep through 5-HTP pathway.
Primary Uses
SleepMood supportSerotonin production
Frequently Asked About L-Tryptophan
How much L-Tryptophan should I take?
The typical effective range is 500-2000 mg daily. Individual needs vary based on age, body weight, diet, and goals โ start at the lower end and adjust based on response. Always consult a healthcare provider before starting a new supplement.
When is the best time to take L-Tryptophan?
Evening for sleep; any for mood. Consistency matters more than perfect timing โ pick a daily anchor (e.g. with breakfast or before bed) and stick with it.
Should I take L-Tryptophan with food?
Small carb helps absorption.
Does L-Tryptophan interact with medications?
Yes โ known interactions include SSRIs, MAOIs - serotonin syndrome risk. If you take any prescription medication, talk to your doctor or pharmacist before starting L-Tryptophan.
What does L-Tryptophan pair well with?
L-Tryptophan stacks well with B6 and Small carb snack โ these combinations either improve absorption or work synergistically toward common goals.
Who should not take L-Tryptophan?
L-Tryptophan should be avoided or used with caution by people with MAOIs and Use caution with SSRIs. Pregnant or breastfeeding women should consult a healthcare provider before use.
What are the side effects of L-Tryptophan?
Most people tolerate L-Tryptophan well. The most commonly reported side effects are Drowsiness and Nausea. Side effects are usually dose-dependent โ lowering the dose often resolves them.
Dosage
Typical range
500-2000 mg daily
Timing
Evening for sleep; any for mood
With food
Small carb helps absorption
Duration
Safe long-term
Special Populations
Sleep issues, mood support
Research & Studies
Search the literature now
We havenโt curated landmark studies for L-Tryptophanyet โ one-click into the primary literature here. PubMedย (RCTs) is usually the highest-signal starting point.
Mechanism of Action
- โข Converted to 5-HTP then serotonin
- โข Serotonin converted to melatonin
- โข Rate-limited by tryptophan hydroxylase
Evidence Quality
Evidence Grade B
Serotonin and melatonin precursor
Safety & Contraindications
Serious Warnings
- โข Serotonin syndrome with SSRIs
Contraindications
- โข MAOIs
- โข Use caution with SSRIs
Common Side Effects
- โข Drowsiness
- โข Nausea
Pregnancy & Breastfeeding
Avoid high doses
Liver & Kidney Notes
Safe
Interactions
๐ Medications
- โข SSRIs, MAOIs - serotonin syndrome risk
๐งช Supplements
- โข 5-HTP similar pathway
๐ฝ๏ธ Food & Alcohol
- โข Turkey is source
Stacking & Synergies
Buying Guide
What to Look For
- โข L-form
- โข Pure
Standardization Markers
L-tryptophan content
Adulteration risk
Low
Practical Notes
- โข Gentler than 5-HTP
- โข Take with carbs for brain uptake
Tags
amino acidessentialsleepmood
Top Products with L-Tryptophan
Highest-scored catalog products containing L-Tryptophan, ranked by our scoring engine.
RecoveryProยฎThorne92
Amino ComplexThorne87
Amino Complex - BerryThorne84
Amino Complex - LemonThorne84
Related Guides
In-depth guides covering L-Tryptophan โ protocols, comparisons, and use cases.
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Last reviewed: June 2026 by the Formulate Research Team. Sources cited above; methodology and scoring criteria published here.
Cite this page
Formulate Research Team. (2026, June). L-Tryptophan โ Evidence-Based Supplement Guide. Formulate Supplement Encyclopedia. https://app.formulate-health.app/learning/supplements/l-tryptophan
Educational content based on published research and our scoring methodology. Not medical advice โ consult a qualified healthcare provider before starting, stopping, or changing supplements, especially if you take medications, are pregnant, or have a medical condition.