Caffeine and Theanine
The short answer. There isn't much data on Caffeine and Theanine yet — 3 mentions, 3 with a clear outcome — so treat these numbers as anecdotal.
Out of 3 mentions; the other 0% didn't say how it went and aren't counted.
What Caffeine and Theanine does, according to users
Of the people who reported each effect, the share who said it got better.
What the research says
Systematic reviews and meta-analyses from PubMed, with their published conclusions.
Dosage people report
As stated by users — not a recommendation. Follow the label or your doctor.
Reported side effects
How often each side effect came up across all reports.
What users say
First-hand experiences, quoted verbatim. We show one positive and one negative where both exist.
“Caffeine and theanine worked pretty well from the two times I've tried it so far.”
“I use pure l-theanine powder about 15 minutes after drinking a cup of coffee...Theanine reduces the negative effects of stimulants.”
“I've found the combination of caffeine and theanine work pretty well in me.”
Other options for focus
User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 3, 2026. How we rate