Ashwagandha and caffeine: what the evidence says about taking them together

No — ashwagandha doesn't contain caffeine, and no trial has tested taking ashwagandha and caffeine together. Some people pair the two on the idea that ashwagandha's calming reputation might smooth out caffeine's jitteriness, but that specific pairing has never been measured in a trial.

What the evidence doesn't support

It doesn't support ashwagandha "canceling out" or reducing caffeine's stimulant effects — no trial has tested that combination. It doesn't support the idea that ashwagandha itself has any stimulant content or caffeine-like effect; it's an herb, evaluated in trials for entirely different outcomes. And it doesn't support using either ingredient, alone or together, as a treatment for anxiety or a stress-related diagnosis.

What the trials found

Ashwagandha's own trials don't involve caffeine at all. A 2012 randomized, placebo-controlled trial gave 64 adults with a history of chronic stress 600 mg/day of a concentrated ashwagandha root extract for 60 days; stress-scale scores and cortisol were lower than placebo by day 60. A 2024 meta-analysis pooling 9 randomized trials, 558 people total, found similar results across stress and anxiety scales and cortisol. None of these trials included a caffeine arm, tested caffeine intake as a variable, or measured jitteriness or alertness.

Mechanistically, ashwagandha's research points toward sedative, GABA-mimetic activity — the opposite direction from caffeine's stimulant effect on the central nervous system. That's a reasonable basis for why people pair them expecting a "balancing" effect, but a plausible mechanism in opposite directions is not the same as a trial measuring what actually happens when both are taken together. No such trial exists.

Questions people ask

Does ashwagandha have caffeine?

No. Ashwagandha is an herb (Withania somnifera root), and it doesn't contain caffeine or any comparable stimulant compound.

Does ashwagandha cancel out caffeine's effects?

No trial has tested this. The mechanisms point in different directions — sedative for ashwagandha, stimulant for caffeine — but that's not the same as evidence that one offsets the other when taken together.

Can you take ashwagandha and coffee or an energy drink together?

No trial has tested ashwagandha alongside caffeinated coffee, energy drinks or other caffeine sources. Nothing in ashwagandha's own trial base addresses that combination directly. See ashwagandha and coffee for more on that specific pairing.

Does ashwagandha interact with caffeine?

No dedicated interaction trial exists between the two. Ashwagandha's own documented cautions — with sedatives, thyroid medication and in pregnancy — don't currently include a caffeine-specific warning, but that reflects an absence of testing rather than a confirmed "no interaction" finding.

When to talk to a doctor

If you're relying on caffeine to manage fatigue or ashwagandha to manage stress, and either isn't working the way you'd expect, that's worth raising with a doctor rather than adjusting doses on your own. Ashwagandha is not a treatment for anxiety or a stress-related diagnosis, and it carries its own cautions, including with sedatives, thyroid medication and in pregnancy.

Related reading: ashwagandha and coffee, ashwagandha benefits: what the research does and doesn't show, and ashwagandha and cortisol.