Caffeine has a comfortable zone and a clear line past it. Cross that line and your body sends unmistakable signals.
Signs you've had too much
- Jitters and shakiness, restlessness, irritability
- A racing or irregular heartbeat, and higher blood pressure
- Anxiety, trouble sleeping, headache
- Nausea or an upset stomach
How much is too much?
Symptoms usually show up above the 400 mg/day mark for adults, or 200 mg in pregnancy, but sensitive people feel them far sooner. A genuine caffeine overdose, with vomiting, confusion and a very fast heartbeat, is rare but a medical emergency, and it's almost always tied to pills or powders, not coffee.
How to come down
- Stop all caffeine for the rest of the day. No more to 'power through.'
- Hydrate and walk it off. Light movement helps.
- Wait it out. With a roughly 5–6 hour half-life, the worst passes in a few hours.
Most overloads are just a mistimed second or third cup. Caffy's live gauge shows when you're nearing your limit, so you can stop before the jitters start.