What are the signs that someone is addicted to amphetamines?

Overstimulated: Users show signs of hyperactivity and nervous energy. They may talk fast and be unable to focus on one thing for any length of time. Their eyes will show pupil enlargement (dilation) and sensitivity to bright lights. Users will have a rapid heartbeat, dry mouth and increased blood pressure.

Any of these: If you are needing more to get high, have withdrawal symptoms or needing to take more to avoid such, spending a lot if time looking for the drug, using is causing you problems socially or with work and you continue to use despite these problems and are unable to stop despite your efforts, you are addicted.