Grass, Weed, Pot whatever you want to call it there are negative effects of Marijuana like it or not.From the memory loss to the addiction itself Marijuana can do a lot of long and short term damage to your brain. One of the short term effects is the higher risk of heart attack. First off the heart attack can and maybe kill you. Secondly when you’re pulled into the hospital they’ll ask if you know what may have caused this… and depending what state you’re in or what country it could get you arrested.