National Institute on Drug Abuse
If a woman is pregnant and smokes marijuana, will it hurt the baby?
Doctors advise pregnant women not to use any drugs because they could harm the growing fetus. One animal study has linked marijuana use to loss of the fetus very early in pregnancy.
Some scientific studies have found that babies born to marijuana users were shorter, weighed less, and had smaller head sizes than those born to mothers who did not use the drug. Smaller babies are more likely to develop health problems. There are also research data showing nervous system problems in children of mothers who smoked marijuana.
Researchers are not certain whether a newborn baby's health problems, if they are caused by marijuana, will continue as the child grows. Preliminary research shows that children born to mothers who used marijuana regularly during pregnancy may have trouble concentrating.
What does marijuana do to the brain?
Some studies show that when people have smoked large amounts of marijuana for years, the drug takes its toll on mental functions. Heavy or daily use of marijuana affects the parts of the brain that control memory, attention, and learning. A working short-term memory is needed to learn and perform tasks that call for more than one or two steps.
Smoking marijuana causes some changes in the brain that are like those caused by cocaine, heroin, and alcohol. Some researchers believe that these changes may put a person more at risk of becoming addicted to other drugs, such as cocaine or heroin. Scientists are still learning about the many ways that marijuana could affect the brain.
Can people become addicted to marijuana?
Yes. While not everyone who uses marijuana becomes addicted, when a user begins to seek out and take the drug compulsively, that person is said to be dependent or addicted to the drug. In 1995, 165,000 people entering drug treatment programs reported marijuana as their primary drug of abuse, showing they need help to stop using the drug.
According to one study, marijuana use by teenagers who have prior serious antisocial problems can quicky lead to dependence on the drug.
Some frequent, heavy users of marijuana develop a tolerance for it. "Tolerance" means that the user needs larger doses of the drug to get the same desired results that he or she used to get from smaller amounts.
What if a person wants to quit using the drug?
Up until a few years ago, it was hard to find treatment programs specifically for marijuana users.
Now researchers are testing different ways to help marijuana users abstain from drug use. There are currently no medications for treating marijuana addiction. Treatment programs focus on counseling and group support systems. There are also a number of programs designed especially to help teenagers who are abusers. Family doctors are also a good source for information and help in dealing with adolescent marijuana problems.
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