Signs and symptoms of teenager drug addiction :

Signs and symptoms:
Change in performance at school or work -- grades dropping, no interest in school activities, missing classes, taking more time off than usual, missing deadlines
Reckless actions without regard to consequences
Withdrawal from family, friends, and activities
Hostility towards others
Missing money or valuable items
Legal issues and arrests
Multiple doctor appointments
Missing medications
Health issues: bloodshot eyes, depression, change in sleep patterns, weight loss, paranoia, hallucinations, shaking and trembling.