Do energy drinks ever cause any heart problems? can you have too many?

Yes and yes: Too many energy drinks can cause palpitations, tachycardia and other heart problems. If you are drinking lots of energy drinks and having heart symptoms, see your doc right away. It's a good idea to limit your consumption of energy drinks.

Yes: Energy drink contains a lot of caffeine and other stimulants. This can cause heart palpitations and arrhythmia, as well as make you more likely to consume excess alcohol by masking its effects. Plus that is a lot of empty calories. Read the label for more info.

Absolutely!: Sorry to burst the "natural" bubble of those energy drinks but the only true "energy" comes from the caffeine. Sure, they will say that they also contain this herb or that vitamin, blah, blah, blah. None are fda approved, though. It's all about the caffeine! and, yes, too much caffeine can cause cardiac arrthymias and elevate your blood pressure. Try to limit them as much as you can!