Caffeine and L-theanine may boost attention in teens with ADHD (not a replacement for meds)

A double-blind, placebo-controlled crossover study in 21 adolescents with ADHD found that a single high-dose combination of L-theanine and caffeine improved selective attention, reduced false alarms, and lessened progressive slowing of responses during a 12-minute task, with EEG suggesting faster target evaluation and greater neural resource allocation. While methylphenidate also reduced false alarms and sped responses, the L-theanine–caffeine combo did not replicate the same speed boost. The researchers caution the findings do not imply this combo should replace established ADHD treatments and call for larger, longer-term studies to assess real-world benefits and safety.