Typical guidance
Common studied range: 1.5–6 g/day; much of the sexual-function evidence is in men.
MODERN BIO / SEXUAL HEALTH / SUPPLEMENT
Moderate evidenceL-citrulline
May modestly support nitric-oxide production and blood flow.
This page is a practical starting point—not a diagnosis or personalized prescription. The useful dose depends on the outcome, the person and the quality of the intervention.
01TYPESupplement
02TYPICAL SERVING / DOSECommon studied range: 1.5–6 g/day; goals and products vary
03TIMINGDaily or 30–60 minutes before exercise
04TRIAL LENGTHReassess response after several weeks
HOW TO USE THIS PAGE
Decide whether l-citrulline deserves a real trial.
- 01Confirm the fit
Connect the intervention to a specific sexual health outcome and review the evidence boundary.
- 02Set the protocol
Define amount, timing, quality standard and a realistic trial length before starting.
- 03Track one useful signal
Choose the measure that will tell you to continue, adjust or stop.
RECOMMENDED RANGES
Men and women may need different context.
We only show a different amount when physiology, dietary requirements or clinical evidence supports it. Otherwise, we say the range is the same.Typical guidance
No established female-specific dose for sexual health. Exercise studies often use similar ranges, but data are more limited.
Important context: Blood pressure, medication use and the target outcome matter more than sex alone.
WHAT IT MAY HELP WITH
Why people use it
May modestly support nitric-oxide production and blood flow. Its relevance here is specifically connected to sexual health. Outcomes can differ when the same intervention is used for another purpose.
Moderate evidence
Promising human evidence exists, but studies, populations or results have meaningful limitations.
SERVING & PROTOCOL
How it is typically used
Common studied range: 1.5–6 g/day; goals and products vary
Citrulline raises arginine availability and may support nitric-oxide production; effects are usually modest.
- Timing
- Daily or 30–60 minutes before exercise
- How long to assess
- Reassess response after several weeks
QUALITY CHECK
What to look for
- A form, device, provider or protocol that matches the evidence—not just the marketing name.
- Transparent labeling, realistic claims and independent quality verification where applicable.
- A measurable reason to use it and a predefined way to judge whether it is helping.
- No hidden proprietary blend or pressure to replace proven medical care.
SAFETY & INTERACTIONS
What to know first
Can lower blood pressure. Review nitrates, PDE5 drugs, antihypertensives and cardiovascular disease with a clinician.
Stop and reassessDiscontinue and seek appropriate care for a severe reaction, fainting, chest symptoms, breathing difficulty, neurological changes or rapidly worsening symptoms.
SCIENTIFIC EVIDENCE
Read the data yourself.
These high-level sources establish the scientific context for sexual health. The live PubMed link narrows the literature to l-citrulline.01Systematic review · 2018
Physical Activity to Improve Erectile Function
Reported that regular aerobic exercise—approximately 160 weekly minutes in the reviewed evidence—can improve erectile function in men with lifestyle-related risk factors.
Open scientific source ↗02Systematic review & meta-analysis · 2011
Lifestyle Modification and Erectile Dysfunction
Found that lifestyle change and cardiovascular risk reduction were associated with improved erectile function.
Open scientific source ↗LIVENATIONAL LIBRARY OF MEDICINE
Search L-citrulline on PubMed
See the current indexed biomedical literature, including newer trials and reviews added after this page was published.
Open live PubMed search ↗Research quality is not determined by citation count alone. We consider design, sample size, controls, consistency, relevance, conflicts and whether the outcome was clinically meaningful.
MODERN BIO SELECT
The best option—regardless of commission.
We do not sell the top placement. Every winner must earn it through evidence, quality, safety, transparency and real-world value.PRODUCT / SERVICE PICKREVIEW IN PROGRESS
Best L-citrulline product
We are comparing formulation, clinically relevant serving, contaminant testing, label transparency, value and manufacturer quality before naming a winner.
Get notified when selected →PROVIDER PICKVETTING IN PROGRESS
Best professional guidance
Our provider directory will prioritize credentialed clinicians and registered dietitians who evaluate the full picture before recommending a supplement.
Join the provider shortlist →What a winner must prove01 Third-party identity and contaminant testing02 A transparent, evidence-aligned serving03 No proprietary blend or inflated claims
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