It was generally thought that even though it was illegal, prolonged use of cannabis caused little or no adverse health effects. Using cannabis during pregnancy can cause premature delivery or abnormal babies. Besides cancer, these carconogenetic ingredients cause bronchitis, emphysema and harms the body's immune system. Users that already have personality or anxiety disorders can have their conditions suddenly worsen with cannabis use. It can cause serious hallucinations which cause you to see or hear things that don't exist.
Emotional problems can suddenly seem overwhelming.
The symptoms of repressed or controlled mental illness can violently resurface. Some users report a sudden fear of death. Your ability to speak, drive a car, read or react intelligently to crisis or emergency, will be seriously reduced. Cannabis use is addictive if consumed regularly. Even for casual users, the addiction may not be physical but psychological, where the drug is used to repress problems that need to be addressed.