L-Citrulline
Amino Acid
Also known as: Citrulline, Citrulline malate
B
Grade B💊 3-6 g citrulline or 6-8 g citrulline malate🎯 4 primary uses🔗 2 synergies⚠️ Review warnings
Levels upMovement+50 pts
Overview
More effective nitric oxide booster than arginine. Converts to arginine while bypassing liver metabolism.
Primary Uses
Blood flowExercise performanceCardiovascular healthPump
Frequently Asked About L-Citrulline
How much L-Citrulline should I take?
The typical effective range is 3-6 g citrulline or 6-8 g citrulline malate. Individual needs vary based on age, body weight, diet, and goals — 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-Citrulline?
30-60 min before exercise. Consistency matters more than perfect timing — pick a daily anchor (e.g. with breakfast or before bed) and stick with it.
Should I take L-Citrulline with food?
Optional.
Does L-Citrulline interact with medications?
Yes — known interactions include BP meds, nitrates - caution. If you take any prescription medication, talk to your doctor or pharmacist before starting L-Citrulline.
What does L-Citrulline pair well with?
L-Citrulline stacks well with Arginine and Beetroot — these combinations either improve absorption or work synergistically toward common goals.
Who should not take L-Citrulline?
L-Citrulline should be avoided or used with caution by people with None. Pregnant or breastfeeding women should consult a healthcare provider before use.
What are the side effects of L-Citrulline?
Most people tolerate L-Citrulline well. The most commonly reported side effects are Well tolerated. Side effects are usually dose-dependent — lowering the dose often resolves them.
Dosage
Typical range
3-6 g citrulline or 6-8 g citrulline malate
Timing
30-60 min before exercise
With food
Optional
Duration
Safe long-term
Special Populations
Athletes, blood flow support
Research & Studies
Search the literature now
We haven’t curated landmark studies for L-Citrullineyet — one-click into the primary literature here. PubMed (RCTs) is usually the highest-signal starting point.
Mechanism of Action
- • Converts to arginine in kidneys
- • Bypasses hepatic metabolism
- • More sustained NO production
Evidence Quality
Evidence Grade B
Superior to arginine for NO production
Safety & Contraindications
Serious Warnings
- • None significant
Contraindications
- • None
Common Side Effects
- • Well tolerated
Pregnancy & Breastfeeding
Consult healthcare provider
Liver & Kidney Notes
Safe
Interactions
💊 Medications
- • BP meds, nitrates - caution
🧪 Supplements
- • Can combine with arginine
🍽️ Food & Alcohol
- • Watermelon is source
Stacking & Synergies
Pairs Well With
Avoid Combining With
None
Best Goal Synergies
Exercise performancePumps
Buying Guide
What to Look For
- • Form specified
Standardization Markers
Pure citrulline vs malate
Adulteration risk
Low
Practical Notes
- • Better absorbed than arginine
- • Found in watermelon
Tags
amino acidnitric oxideperformancepump
Related Guides
In-depth guides covering L-Citrulline — 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-Citrulline — Evidence-Based Supplement Guide. Formulate Supplement Encyclopedia. https://app.formulate-health.app/learning/supplements/l-citrulline
Educational content based on published research and our scoring methodology. Not medical advice — consult a qualified healthcare provider before starting, stopping, or changing supplements, especially if you take medications, are pregnant, or have a medical condition.