Caffeine can raise anxiety, and the studies say it does so most clearly at high doses and in people with panic disorder. A meta-analysis of healthy people found that caffeine increased anxiety overall, with a larger effect above 400 mg, [liu-2024] and a review of challenge studies found 51.1% of patients with panic disorder had a panic attack after caffeine and none after placebo. [klevebrant-2022] This guide covers both reviews, what the doses meant, what the studies could not show and how to test your own pattern. Our overview of anxiety covers the wider picture.
Does caffeine cause anxiety in healthy people?
It raised anxiety on average, with a bigger effect at higher doses. Liu and colleagues pooled studies in healthy people without psychiatric disorders, and 14 studies from eight articles, with 546 participants, went into the caffeine and anxiety analysis. Caffeine intake increased anxiety overall, with a standardised mean difference of 0.94 (95% confidence interval 0.28 to 1.60). [liu-2024]
By dose, low-dose caffeine moderately increased anxiety (0.61, 95% confidence interval 0.42 to 0.79), while high-dose caffeine had a much larger effect (2.86, 2.50 to 3.22). The authors concluded that caffeine intake is associated with elevated anxiety in healthy people, especially above 400 mg. [liu-2024] On the usual rule of thumb, 0.2 is a small effect and 0.8 a large one, but the wide interval around 0.94 shows how uncertain the pooled figure is.
Can caffeine trigger panic attacks?
In people with panic disorder, it can. Klevebrant and Frick pooled blinded, placebo-controlled studies of a single caffeine dose in adults with panic disorder. Of 1,893 articles identified, ten met the criteria. In the nine studies of panic attacks, covering 237 patients, 51.1% had a panic attack after caffeine and none had one after placebo. [klevebrant-2022]
Six studies compared 128 patients with 115 healthy controls. Panic attacks followed caffeine in 53.9% of patients and 1.7% of controls (log risk ratio 3.47, 95% confidence interval 2.06 to 4.87). Subjective anxiety also rose more in patients (Hedges’ g = 1.02, 0.09 to 1.96), and caffeine increased anxiety in healthy adults as well at these doses. [klevebrant-2022]
Six studies that compared 128 patients with panic disorder and 115 healthy controls, in Klevebrant and Frick (2022). Doses ranged from 400 to 750 mg, roughly equivalent to five cups of coffee at 480 mg.
| Review | Who | Dose tested | Main finding |
|---|---|---|---|
| Liu 2024 | Healthy people, 14 studies, 546 people | 0 to 460 mg | Anxiety up overall (0.94), more so above 400 mg |
| Klevebrant and Frick 2022 | Adults with panic disorder, 237 patients | 400 to 750 mg | 51.1% had a panic attack after caffeine, none after placebo |
How much caffeine is too much for anxiety?
The reviews could not say. The healthy-population review notes that its limited dose range, 0 to 460 mg, prevented any meaningful analysis of a dose-response relationship. [liu-2024] The panic disorder review tested 400 to 750 mg, with only three studies using a dose other than 480 mg, which prevented a dose-response analysis there too. [klevebrant-2022]
That 480 mg is described as roughly equivalent to five cups of coffee. The authors add that little is known about doses smaller than 480 mg, and that clinicians should tell patients with panic disorder about the panicogenic and anxiogenic effects of caffeine with that caveat. [klevebrant-2022] Sensitivity also differs between people: 53.9% of patients had a panic attack against 1.7% of controls on the same kind of dose.
What do the studies not show about caffeine and anxiety?
They do not show what a daily habit does, and they do not show that cutting back reduces anxiety. Almost all the included studies gave a single dose in a lab or class setting. The exception was one cross-sectional study of daily coffee intake in middle school students in the healthy-population review. [liu-2024] [klevebrant-2022] Only two of the ten panic disorder studies reported anxiety data for the placebo condition, which prevented a proper comparison of caffeine against placebo on subjective anxiety. [klevebrant-2022]
The healthy-population review lists its own limits: high heterogeneity between studies, little control for factors such as sex (some studies suggest caffeine raises anxiety in males but not in females), and a restricted dose range. [liu-2024] Neither review tested a treatment. They show an association and an acute effect, and the rest is for your own diary and your doctor.
How can you check your own caffeine pattern?
Keep a two-week diary of what you drink and how you feel in the next few hours. That is our adaptation of the reviews, not a method they tested, and it works because sensitivity varies so much between people. Write down cups of coffee, tea, energy drinks and cola, the time, and any jitteriness, racing heart, worry or panic.
Is caffeine worth cutting back for you?
Tick anything that is true for you most weeks. This is a prompt for reflection, not a test, and it produces no diagnosis.
0 of 5 ticked
Several of these together suggest caffeine may be adding to how anxious you feel. Try the two-week diary, and if panic attacks are part of it, mention caffeine to a doctor.
One or two of these is common. Keep an eye on whether the pattern tracks your intake before changing anything.
Nothing on this list applies right now. If anxiety is still a problem, caffeine is unlikely to be the whole story.
If panic attacks are a regular part of your life, our guide to how often panic attacks happen covers what is typical, and our overview of panic attacks covers what they are.
When to seek help
Speak to a doctor if anxiety or panic is affecting your sleep, work or relationships, whatever your caffeine intake, and say specifically how much caffeine you have. Our guide to the difference between nervous and anxious covers where ordinary nerves end. If you feel unable to keep yourself safe, contact your local emergency services or a crisis helpline.
How MyFreud can help
A caffeine diary only helps if you keep it going. Daily mood tracking in MyFreud shows how your days go over a couple of weeks, and the notepad is somewhere to log what you drank next to how you felt. It does not replace a doctor.
Download MyFreud and start today: App Store or Google Play.