What do the states mean?+
- Solid: well studied, and it works.
- Half-there: the science is still forming.
- A ghost: almost no real studies.
- Hollow: well studied, and it does not work.
- A cord: the pair itself has been tested together.
- Air: nobody has ever tested this pair.
The full scoring method: How we score
Can you take creatine monohydrate and L-arginine together?
You don’t need to take them together.
As of August 2026, creatine monohydrate and L-arginine have been tested together in 1 trial, in adults with coronary artery disease, and no clear added effect was found. Scored under the same rules as everything here.
44 studies · 1 tested the actual pair · 2 cautions
What you’re seeing
- Creatine monohydrate renders solid: for strength and power, it is well studied and it works.
- L-arginine renders half-there: for endurance, the science is still forming.
- The woven cord is the rare part: one trial gave both together, and no clear added effect was found.
You can tell before you read a word.
Magnesium + L-theanine are sold together in the same aisle. No trial has ever tested the pair. When that is true, we draw nothing between them. The nothing is the review.
The pair trial
- 2009Randomized trial · adults with coronary artery disease · no clear effectsource
The other 43 studies on file tested each one alone. See all 44 studies
Fair questions
Is it safe to take creatine monohydrate and L-arginine together?+
The studies on this page gave both together and reported no harm from the combination. That is not the same as a safety trial, and it says nothing about your dose or your medication.
How many studies is this based on?+
1 that gave the pair together. The papers are listed above with links to the source.
Deeper
What each one is on its own+
Creatine monohydrate
- Strength and powersolid
- Endurancehalf-there
- Memory and focushalf-there
- Muscle in older adultshalf-there
- Muscle sizehalf-there
- Sprint and repeated-effort powerhalf-there
- The hair-loss worrya ghost
L-arginine
- Endurancehalf-there
- Asthma and breathinghalf-there
- Blood pressurehalf-there
- Cholesterolhalf-there
- Gut and digestionhalf-there
- Hearthollow
- Immunity and coldshalf-there
- Inflammationhalf-there
- Performance and vitalityhalf-there
- Pregnancya ghost
- Sprint and repeated-effort powerhalf-there
- Strength and powerhalf-there
- Testosterone and libidohalf-there
- Weight and body fathollow
- Wound healinghalf-there
Pairs that have been tested+
- Creatine monohydrate has been tested with folate, taurine, beta-alanine, NAC, 5-HTP.
- L-arginine has been tested with L-theanine, selenium, L-lysine, L-glutamine, probiotics, vitamin C.
These are the combinations someone has actually run a study on. Every other pairing here is air.
Worth knowing+
- Creatine monohydrate: Kidney disease: ask your doctor first. In healthy people, trials at label doses keep coming back clean.
- L-arginine: Searching 21 health outcomes returned no trial of L-arginine on its own for any of them. This is not the same as a supplement nobody has studied. L-arginine is a nutrient your body needs, and there is research on it. What that research is about is multi-antioxidant fertility formulations and clinical nutrition, rather than arginine taken alone. None of it tells you whether taking extra helps someone who already gets enough.