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    Daily Pot Smokers Court Health Risks

    Study Shows Regular Marijuana Users Have Risk of Respiratory Problems and Psychoses

    Marijuana and Health

    In the medical literature review, Hall found:

    • About 9% of those who ever use marijuana become dependent. But the risk rises to one in six if use begins in teen years. About 10% of ever-users become daily users, and 20% or 30% become weekly users.
    • Driving after smoking marijuana increases the risk of a motor vehicle accident by two to three times, research suggests, while driving after drinking alcohol increases accident risk six to 15 times.
    • Symptoms of chronic bronchitis were more commonly reported among regular marijuana smokers than nonsmokers. The smokers reported wheezing, chronic cough, and production of sputum.
    • Studies looking at a possible link between an increased risk of cancers in the upper respiratory tract and marijuana use have produced mixed findings, with some finding a link and others not.
    • Marijuana use increases the heart rate, and adults with existing heart disease may be at higher risk of a heart attack after pot use, some research suggests.
    • Regular marijuana users, especially if they started at a young age, are more likely to later use other drugs such as heroin and cocaine, according to some studies.
    • Regular and heavy pot use has been linked with problems in memory, attention, and verbal learning, but researchers aren't certain whether those changes are transient and disappear once marijuana use is stopped.
    • The use of marijuana by age 18 is linked with more than a doubling of risk for a later diagnosis of schizophrenia, according to a large Swedish study.
    • Early marijuana use, before age 15, has been linked with school dropouts. But researchers are unsure exactly how to explain the association. One possibility: poor school performance can trigger the pot use, which in turn makes school performance even worse.
    • Smoking pot during pregnancy has been linked with underweight babies, but there is little evidence it's linked to birth defects.

    Avoiding Health Risks of Marijuana

    Hall notes that some people are at greater risk for adverse health effects from smoking marijuana, especially "young persons under the age of 18 and ... persons with any disease or condition (for example, pregnancy, cardiovascular or respiratory disease, mental illness, or other types of substance abuse) which increases their vulnerability to its adverse effects."

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