What causes adhd?

Genes: Most cases (> 95%) of adhd are inherited and worsened by prenatal events such as prematurity, smoking, neonatal illness or stress. Rarely, a brain injury or insult can result in "acquired" adhd. This would include chemobrainsuch as from cancer treatment, of after an infection such as meningitis or encephalitis, or an injury such as concussion or brain contusion or hematoma.

Not Known: Although there is clearly a genetic component to add/adhd the cause is truly unknown at this time. There are conditions that mimic , but the true causes need to be determined.

ADHD: No single specific etiology. Most accepted theory is combination of biological-psychological-social attributes.