Amino Acid
L-Citrulline
Also known as: Citrulline, Citrulline malate
More effective nitric oxide booster than arginine. Converts to arginine while bypassing liver metabolism.
Last reviewed June 2026 · Evidence graded from peer-reviewed research, not editorial opinion. Educational only — not medical advice.
Every L-Citrulline product we have scored
| # | Product | Score | Per serving |
|---|---|---|---|
| 1 | BulkSupplements L-Citrulline Powder | 91 A | $0.07 |
| 2 | Transparent Labs BULK Pre-Workout | 90 A | $1.67 |
| 3 | Nutricost Pre-Workout For Women Powder | 89 A | $0.73 |
| 4 | Nutricost Pre-Workout Complex | 89 A | $0.83 |
| 5 | Double Wood L-Citrulline Supplement | 88 A | $0.19 |
| 6 | NOW Foods L-Citrulline Pure Powder | 87 A | $0.28 |
| 7 | Onnit Total Nitric Oxide - Harvest Fruit (20 Serving Tub) | 85 A- | $2.00 |
| 8 | BulkSupplements L-Citrulline DL-Malate 1:1 Powder | 84 A- | $0.26 |
| 9 | Micro Ingredients L-Citrulline Malate Powder | 84 A- | $0.17 |
| 10 | Pure Encapsulations Nitric Oxide Support | 82 A- | $1.70 |
| 11 | Gorilla Mind Gorilla Mode Nitric | 82 A- | $1.50 |
| 12 | Pure Encapsulations Nitric Oxide Ultra (capsules) | 78 B+ | $1.43 |
Scored on dose accuracy, form, label transparency and third-party testing. Per-serving cost is list price divided by servings per container. No brand pays to be listed or ranked.
Common questions
How much L-Citrulline should I take?
The typical range is 3-6 g citrulline or 6-8 g citrulline malate. Safe long-term
When should I take L-Citrulline?
30-60 min before exercise. Optional.
Which form of L-Citrulline is best?
Powder — Often in pre-workouts. Other forms in the catalog: Citrulline malate.
Is L-Citrulline safe?
Commonly reported: Well tolerated. Serious warnings: None significant. Safe
Which L-Citrulline supplement scores highest?
BulkSupplements L-Citrulline Powder, at 91/100. Scored on dose accuracy, form, label transparency and third-party testing — no brand pays to be listed or ranked.
Daily target & upper limit
6 g / dayL-Citrulline has an established daily reference intake. See best forms, label synonyms, upper-limit warnings, and top-scoring supplements:
L-Citrulline dosage reference →Primary uses
- Blood flow
- Exercise performance
- Cardiovascular health
- Pump
What systematic reviews concluded
Outcomes that systematic reviews of L-Citrulline reached a verdict on: 3 with a benefit, 3 with no effect, 8 unclear. Each is quoted from a review and linked to it on PubMed. How these were read.
Reviews found a benefit (3)
“The current analysis observed a small ergogenic effect of CitMal compared with placebo.” PMID 34010809
“Citrulline supplements significantly reduced post-exercise RPE and muscle soreness without affecting blood lactate levels.” PMID 33308806
“Supplementing with 6-8 g of CitMal 40-60 min before exercise increased repetitions by 3 ± 5 (6.4 ± 7.9%) compared with placebo (p = .022) with a small SMD (0.196).” PMID 34010809
Reviews found no effect (3)
“In conclusion, our systematic review and meta-analysis found that L-Citrulline and L-Arginine did not influence inflammatory biomarkers and oxidative stress after exercise.” PMID 37111214
“citrulline malate supplementation does not improve muscle strength in healthy and resistance-trained individuals” PMID 34176406
“Citrulline supplements significantly reduced post-exercise RPE and muscle soreness without affecting blood lactate levels.” PMID 33308806
Not enough to say: body composition; blood pressure; blood lactate; endurance exercise performance; exercise performance; perceived exertion.
How it works
- Converts to arginine in kidneys
- Bypasses hepatic metabolism
- More sustained NO production
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
Forms
- Powder
- Citrulline malate
Safety
Common side effects
- Well tolerated
Contraindications
- None
Products containing L-Citrulline
Top-scoring supplements in our catalog that list L-Citrulline on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.
Evidence notes
Superior to arginine for NO production
Grade B: Some human trials support key claims; further confirmation needed.
Related in Amino Acid
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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Individual needs and risks vary — consult a professional before starting, stopping, or combining supplements, especially if you are pregnant or nursing, taking medication, or managing a health condition.