Understanding the interactions, benefits, and safety of combining these two powerful supplements.
We found no documented interaction between Citrulline and L-theanine in the sources below. That isn't proof the combination is right for you: check each one's cautions, and ask your pharmacist if you take medication.
What it is: An amino acid the body makes. The kidneys turn most of it into arginine, and then nitric oxide.
What the research says: Research on it as a performance supplement is limited and mixed.
In Holitro: Citrulline (500 mg per capsule)
Source: NIH Office of Dietary Supplements: Dietary Supplements for Exercise and Athletic Performance (updated March 2021)
What it is: An amino acid found in green tea, taken for calm and sleep.
What the research says: Small studies suggest it may improve sleep; results for anxiety are mixed.
In Holitro: Theanine 200mg (200 mg per capsule)
Source: Memorial Sloan Kettering Cancer Center, About Herbs: L-Theanine (updated July 2026)
Check with your doctor or pharmacist, especially if you take medication.
Check your stack — freeEducational information only, not medical advice. This reflects general ingredient overlap, not a personalized safety review. Always check with your doctor or pharmacist before combining supplements, especially if you take medication, are pregnant or nursing, or manage a health condition. These statements have not been evaluated by the FDA.
Balancing dosages across multiple different bottles is risky, inefficient, and expensive. Theanine is already lab-dosed and delivered daily in our Sleep Pack — one less bottle to manage.
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