A young brain
The brain keeps developing until about the age of 24 and is extra vulnerable to the effects in that time. The younger someone starts, the greater the chance of addiction and of mental health problems later. Young people who use regularly often do worse at school.
Mental health problems
Use is strongly discouraged for people prone to psychosis, depression or anxiety. If a family member has had a psychosis, your own chance of a psychosis after use is also higher. Existing problems can get worse through use.
Pregnancy and breastfeeding
During pregnancy and while breastfeeding it is best not to use cannabis. It can affect the brain and the growth of the baby. Second-hand smoke is also very unhealthy for a baby, before and after birth.
Dependence
Physical dependence hardly occurs with cannabis. Psychological dependence does: you feel you cannot feel well or function properly without it, you keep wanting it and you think about it often. Anyone who uses every day and cannot stop is psychologically dependent.
Breaking the habit
If you use every day, try not to use on at least two days a week to break the habit. Even better is to keep it to special occasions. Cut down or stop if you notice that your social contacts or your performance suffer.
Stopping, and where to find help
Stopping can be hard: you may get headaches, sweating, shaking, insomnia and restlessness, and you dream a lot. The first week is the hardest and after about two to three weeks the symptoms ease. With questions about use, your own or someone else's, you can go anonymously to the Drugs Infolijn by phone, chat or e-mail, or to your GP.
Sources
- Drugs Infolijn (Trimbos Institute): the consequences of using cannabis at a young age (in Dutch)
- Drugs Infolijn (Trimbos Institute): cannabis and pregnancy (in Dutch)
- Drugs Infolijn (Trimbos Institute): if you use cannabis every day, are you addicted? (in Dutch)
- Drugs en Uitgaan (Trimbos Institute): reduce the risks of hash and weed (in Dutch)
You have read this chapter.
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The facts from the Remember boxes come back in lesson 3. Every question you get right first time earns 10 XP.

