Drug abuse affects your family in ways that are harmful and damaging, but your teen isn’t abusing drugs out of malice. Addiction is a disease that compels them to seek out and take drugs, despite the negative consequences. Once a teenager is addicted to drugs, the brain and body have undergone changes that make it hard to stop. The disease then spreads to the rest of the family because it’s a system of closely related parts. Once one part is affected, all are affected.