What Drugs Cause Red Eyes and Dilated Pupils? | Sober College

What Drugs Cause Red Eyes and Dilated Pupils? | Sober College: One of the first signs of drug use is noticeable changes to the eyes (bloodshot, dilated pupils, etc.). If you suspect a loved one might be using, learn how to observe the shape, size, and appearance of their eyes to determine the possible cause, and help bring them one step closer to treatment and a better life.