I drink energy drinks that contain caffeine.  Can you elucidate on the pros and cons of caffeine consumption?
Well caffeine is legal and unregulated almost everywhere, unlike other psychoactive substances, so that sure is a con.
i sometimes feel out of it when i drink too many, almost like an overdose.  Is there a limit on how much caffeine i should consume?
Definitely, caffeine is a psychoactive drug and should be consumed in limited quantity. The exact amount depends on the person though.
You are saying that caffeine is a drug like heroin?  I wish that i had known this years ago.  I am an addict.
That's right, a psychoactive drug is any psychotropic chemical substance that changes brain function. It can change mood, perception, consciousness or behavior too.