Exact cause of ADHD is not known. Factors that have been implicated include the following:
- Genetics: ADHD has been known to run in families.
- Environmental factors: Exposure to lead, found in paint, has been seen to increase the incidence of ADHD. Cigarette smoking or alcohol abuse in pregnancy also increases risk of ADHD in the child.
- Food additives: Certain food additives have been implicated in the causation of ADHD.