Here is some more good info. I had found this link in another thread when I was looking up the blood pressure effects.

Marijuana Health Mythology
Snorbel Reviewed by Snorbel on . What exactly does weed do? I was curious to what exactly it does to your body when you smoke weed I heard somewhere your blood pressure is raised, which explains the red eyes I know it affects the Nervous system... And that's basically it. If anybody who knows more I'd like to hear..... Rating: 5