They can use the amount they need without bad effects from higher doses. Smoking marijuana causes most of the same health problems as smoking tobacco. Smoked or eaten marijuana can disrupt balance, physical coordination and visual perception. This can make it dangerous to drive a car or operate machinery. This effect can be stronger when marijuana is eaten than when it is smoked.
Some users develop a tolerance to marijuana.
This means they need higher and higher doses to get the same effect. Users can also become dependent on marijuana. They may have mild withdrawal symptoms when they stop using it. There are no known interactions between marijuana and medications or other herbs. However, very few interactions between herbs and medications have been studied.