Cannabis is one of the most commonly used drugs in Britain. But do you know what it is and how it affects your body?
Cannabis can cause feelings of anxiety, suspicion and panic
What is it?
Cannabis comes in many different forms. Hash or solid is cannabis resin, which is a dark or light brown solid. Marijuana or grass is the dried leaves and flowers of the plant. Some varieties of the cannabis plant are more potent, and these are often referred to as skunk.
More recently there has been an increase in strong strains of weed, including skunk and some 'homegrown' varieties. They can be stronger than normal weed and often have a more potent smell.
Cannabis can be smoked with or without tobacco. It is either rolled up in cigarette papers as a joint, or smoked from a pipe, or bong (water pipe).
Some people bake hash in cakes, drink it in tea or just eat it on its own.
How does it make you feel?
Cannabis can make you feel chilled. Your senses may be heightened and it can make you feel really hungry.
Some people have one or two drags on a joint and feel light-headed, faint and sick. This is sometimes called a 'whitey'. Cannabis can also cause feelings of anxiety, suspicion, panic and paranoia.
What are the health effects?
Tobacco and cannabis share some of the same chemicals, so, like smoking tobacco, smoking cannabis can make asthma worse, can cause wheezing in people without asthma and can lead to lung cancer. Like tobacco, it's also addictive. If you develop a tolerance and try to stop using cannabis, you may experience withdrawal symptoms like mood changes, cravings and difficulty sleeping.
Regular cannabis use puts you at risk of later developing psychotic illnesses including schizophrenia. If you have a family background of schizophrenia, you may also have an increased risk.
Some people use cannabis to relieve the symptoms of multiple sclerosis or chronic pain.
Cannabis is an illegal class B drug. The maximum penalty for possession is up to five years in prison, and for supply you can get 14 years in prison and an unlimited fine. Even giving it to your friends is deemed 'supplying' in the eyes of the law.
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This factfile was updated on 15 May 2018