This provides a list of possible substance use warning signs. This is a general list and they can be warning signs for other mental health disorders as well. If a child claims not to be using substances, it is recommended to see the child’s doctor or a psychologies for further assessment. Keep in mind that a child may not be using substances if they has any or all of these warning signs. There may be other things going on in the child’s life. It could also be signs of other mental health disorders as well.