The primary symptoms of ADHD are hyperactivity, impulsivity and inattention. While in normal children, these symptoms can appear in low levels, in children suffering from ADD, these are severe, and occur repeatedly for a long period of time. However, as many of these symptoms can be found in normal children, it is even more important to ensure you get a thorough examination by a qualified mental health professional.

As stated above, in the case of ADHD all of these primary symptoms will be severe and of long duration. For individuals suffering from ADHD with hyperactivity, symptoms of hyperactivity and impulsivity will appear prior to symptoms of inattention. The symptoms of a child with hyperactive ADHD will be much more visible than those of a child with inattentive ADD, who may be regarded as a space cadet.

A child who is impulsive may be viewed as having a behavior problem, while a child who is quiet and spacey will be viewed as lazy and unmotivated. However, these are both cases of ADD, despite the fact that they look very different. Because there are so many variations in ADD and how it manifests itself, it can difficult to diagnose. And the problem is, that the longer you go without being diagnosed, the more complex ADD starts to look, and the more the individual will suffer from it before receiving appropriate treatment.

Signs of hyperactivity/impulsivity are restlessness, distractibility, interrupting and saying things without thinking and being excessively physical. As a child gets older, the impulsivity side of their ADD will take a more damaging toll if not dealt with. Impulsive ADDers tend to get into drugs, break the law and do other destructive things at an earlier age.

Signs of inattention include getting easily distracted, making careless mistakes, becoming easily disorganized, the inability to follow directions correctly and poor follow-through. Also, inattentive ADD sufferers easily become bored, which leads to task switching. Individuals having inattentive ADD usually go the longest without getting diagnosed, as their symptoms are less visible and less distracting to their surrounding environment. However, this does not mean that the disorder is any less disabling for the individual. Persons with inattentive ADD have a higher rate of anxiety and depression because they tend to internalize their symptoms to a greater extent.

If an individual has Combined Type ADHD, they will exhibit almost all of the symptoms of hyperactivity, impulsivity and inattention. These are the most severe cases of ADD, and can be difficult to treat. Combined type ADD sufferers find it very difficult to get organized. They also have the highest chance of not doing well in school, being regarded as a behavior problem for teachers and parents, and also tend to have problems with social skills.