According to:According to the 199 NIH study marijuana is not physically addictive and has medicinal qualities so we know that anyone who claims it is addictive is lying.
Web M.D. Dec 1st, 2010
Physiological Effects of Marijuana
The active ingredient in marijuana is THC. That's short for delta-9-tetrahydrocannabinol.
THC is rapidly absorbed after smoking pot. Within minutes, THC and the other substances in marijuana smoke cause short-term medical effects.
Signs of using marijuana include:
* rapid heart rate
* increased blood pressure
* increased rate of breathing
* red eyes
* dry mouth
* increased appetite, or "the munchies"
* slowed reaction time
These effects are reduced after three or four hours. However, marijuana hangs around in your system for as long as 24 hours after smoking. The lingering effects mean you're impaired for several hours after the high wears off.
Psychological Effects of Marijuana
The main psychological effect of smoking pot is euphoria. Getting high or "stoned" is the reason most pot smokers use marijuana.
Other short-term psychological effects of pot include:
* distorted sense of time
* magical or "random" thinking
* short-term memory loss
* anxiety and depression
These psychological signs of using pot also generally ease after a few hours. But residual effects can last through the next day.
Risks of Marijuana Use
The risks of smoking marijuana go up with heavy use. Although the link has never been proven, many experts believe heavy pot smokers are at increased risk for lung cancer.
Heavy marijuana use lowers men's testosterone levels and sperm count and quality. Pot could decrease libido and fertility in some heavy-smoking men.
Contrary to what many pot smokers may tell you, marijuana is addictive, at least psychologically. Even among occasional users, one in 12 can feel withdrawal symptoms if they can't get high when they want to. Among heavy pot smokers, the rates of dependence are higher.
Many experts also believe that marijuana is physically addictive. Symptoms of withdrawal from pot might include:
* depressed mood
* decreased appetite
Is pot a "gateway" drug? In other words, does smoking marijuana make someone more likely to try cocaine, heroin, ecstasy, and other "hard" drugs? The jury is still out on this one. It's true that pot smokers are more likely to use other drugs after trying marijuana.People who start smoking pot does causes further drug use, people who start smoking pot are just more likely to try drugs in general.
If you're wondering how long marijuana stays in your system after smoking, it depends on how often you smoke. Light users -- those who smoke pot once in a while -- will have a negative drug screen after a marijuana-free week. Heavy users -- sometimes called "stoners" -- may continue testing positive for a month after last smoking pot.