My evenings have completely changed
I used to be useless after 7pm. Now I have energy into the evenings and actually enjoy time with my family rather than just surviving until bedtime. Stack has genuinely changed my quality of life.
Nour M.
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Amino Acid500mg
Citrulline
ENDURANCE BOOSTER & BLOOD FLOW OPTIMIZER
Dairy freeGluten freeSoy freeGMO free
$14.99/mo
30-day supply
Key Benefits
1
Boosts nitric oxide for improved blood flow
2
Enhances exercise endurance and power output
3
Supports post-exercise recovery
4
Promotes cardiovascular health
Wellness Goals
Recommended Dose
500mg
Take one 500mg capsule daily. For exercise performance, take 45-60 minutes before training. Citrulline can be taken on an empty stomach and is well-tolerated. For enhanced effects, it pairs well with arginine.
Get your personalized dose⚗️
3rd Party Tested
🩺
Doctor Formulated
🛡️
cGMP Certified
The Details
Why you'll love it
Here's a counterintuitive fact: if you want to raise your arginine levels and boost nitric oxide, taking citrulline is actually more effective than taking arginine itself. That's because citrulline bypasses liver metabolism and converts to arginine in the kidneys, resulting in a more sustained and reliable increase in circulating arginine and nitric oxide.
The performance benefits are well-documented. Studies show citrulline supplementation increases time to exhaustion during high-intensity exercise, improves power output, and reduces the perception of effort — meaning the same workout feels easier. It also accelerates the clearance of ammonia and lactate, metabolic byproducts that contribute to fatigue and muscle burn.
Beyond the gym, citrulline supports cardiovascular health through its nitric oxide-boosting effects. Better blood flow means better nutrient delivery, waste removal, and vascular function. It's one of the most evidence-backed ergogenic supplements available, and it works for both strength and endurance athletes.
Research
Clinical Evidence
Key studies supporting Citrulline, from peer-reviewed journals.
1
L-citrulline significantly lowers systolic blood pressure
Effects of L-citrulline supplementation on blood pressure: a systematic review and meta-analysis — 2019
2
Citrulline boosts aerobic performance and lowers perceived effort
Effects of citrulline supplementation on different aerobic exercise performance outcomes: a systematic review and meta-analysis — 2022
Study titles are simplified for readability. Provided for informational purposes — not medical advice.
Transparency
What's Inside
Third-Party Tested
Every batch is independently tested by ISO-17025 accredited labs for purity, potency, and contaminants.
Doctor Formulated
Designed by healthcare professionals using evidence-based research and clinical expertise.
cGMP Certified
Manufactured in cGMP & UL certified, FDA-registered facilities with a flawless inspection record.
Important Information
Contraindications
- blood pressure medication
If you take blood pressure medication, consult your healthcare provider before use.
As with any natural health product, consult your healthcare practitioner. Store in a cool, dry place. Keep out of reach of children. Discontinue use immediately if you experience an adverse event.
What people say
changed my whole routine tbh
used to take like 5 different supplements every morning and always forgot at least two of them. now i take one stack pack and that's it. so much simpler. and the results are actually better. wild.
Hazel B.
The value proposition is actually excellent
I calculated what I was spending on separate supplements, gym supplements, and energy drinks before Stack.
Tim A.
Simple, smart, and it actually works
The packaging is some of the nicest I've seen in wellness. But beyond aesthetics, the product delivers. My energy throughout the day is more stable and I'm recovering faster from workouts. I was genuinely skeptical.
Ashley N.
The inflammation reduction has been significant
I suffer from low-grade chronic inflammation and it affects everything - energy, mood, joint comfort. Stack's personalized formula has noticeably reduced these symptoms over three months. The targeted approach is clearly more effective than generic options.
Eric T.
My husband noticed before I did
About six weeks in my husband said I seemed more like myself - more energy in the evenings, less irritable, sleeping better. I hadn't even consciously registered how much had changed until he said it.
Amara S.
Personalized for you
Not sure if Citrulline is right for you?
Take our 2-minute Health Assessment and let our AI build your personalized stack — every supplement chosen for your specific goals.
Take the Health AssessmentProduct images are for illustrative purposes and may not represent actual packaging.
