Doctors say it is possible to overdose on caffeine.
It is called caffeine poisoning and it is a lot like food poisoning.
Symptoms include breathing trouble, fever, even hallucinations, an irregular heartbeat and dizziness. It can even cause death in extreme causes.
Some of those side effects are possible if you are downing more than 500 milligrams of caffeine each day. The best way to avoid it is to stick to the caffeine dosage doctors recommend; 200 to 300 milligrams per day which equals out to two to four cups of coffee.