Symptoms:

Children with conduct disorder tend to be impulsive, hard to control, and not concerned about the feelings of other people.

Symptoms may include:

• Breaking rules without obvious reason
• Cruel or aggressive behavior toward people or animals (for example: bullying, fighting, using dangerous weapons, forcing sexual activity, and stealing)
• Failure to attend school (truancy -- beginning before age 13)
• Heavy drinking and/or heavy illicit drug use
• Intentionally setting fires
• Lying to get a favor or avoid things they have to do
• Running away
• Vandalizing or destroying property

These children often make no effort to hide their aggressive behaviors. They may have a hard time making real friends.

Signs and tests:

There is no real test for diagnosing conduct disorder. The diagnosis is made when a child or adolescent has a history of conduct disorder behaviors.

A physical examination and blood tests can help rule out medical conditions that are similar to conduct disorder. Rarely, a brain scan may also help rule out other disorders.