Giving the child medicine before the pain returns gives better pain relief with fewer side effects. If you wait until the pain starts before giving the medicine, your child will probably need a higher dose to become comfortable again. Once the cause of the pain is removed and the child no longer has pain, pain medicine may not be needed. At that time, the pain medicine can be stopped. A child in pain needs relief.
Many pain medications require higher doses after a few days.
This is not addiction. The body becomes better at getting rid of the medicine and more is needed for the same effect. However, addiction does not occur in children with cancer when they take narcotic medicines for pain. Some types of pain medicines can cause an upset stomach if taken between meals. To prevent stomach upset, try to take medicines with food.