• When stoned, the user’s eyes become red and the heart beats faster.

• It can make users paranoid and anxious, depending on their mood and situation.

• Mixing cannabis with tobacco and smoking it damages the airways and lungs and can lead to users getting hooked on tobacco.

• Inhaling deeply and holding the smoke in, or sucking on a bong or water pipe, increases the amount of tar and other dangerous chemicals which stick to lung tissue.

• Smoking cannabis over a long period of time can increase the risk of respiratory disorders, including lung cancer.

• Plastic bottles, rubber hoses, PVC, aluminium drinks cans or tinfoil, should not be used to smoke cannabis. These all give off toxic fumes when hot.

• Some infections, such as hepatitis, can be passed on if several people are sharing the same joint.

• Cannabis affects the short-term memory and ability to concentrate and make judgements.

• The user may also be affected by cannabis the next day, and it may be more difficult to perform important tasks that require a clear head or sharp reactions.

• Getting stoned affects co-ordination, increasing the risk of accidents. It impairs driving skills, so never get into a car driven by someone who is stoned.

• If cannabis is used with alcohol the risk of becoming ill is increased.

• Users should not use cannabis around others who may be affected by the smoke, particularly children. Low levels of cannabis have been found in the urine of young children.