Steven Kazmierczak had been taking three drugs prescribed for him by his psychiatrist, the Northern Illinois University gunman's girlfriend told CNN. Jessica Baty said Steven Kazmierczak was irritable but not erratic before his shooting rampage. Jessica Baty said Tuesday that her boyfriend of two years had been taking Xanax, used to treat anxiety, and Ambien, a sleep agent, as well as the antidepressant Prozac. Baty said the psychiatrist prescribed the medications, a fact that made her so "nervous" that she tried to persuade Kazmierczak to stop taking one of the drugs.