This is to Colleen and Don. I have been on selegeline for the last 10 months and take it in the morning and at noon. If I forget my noon dosage and take it later in the afternoon, I have no trouble sleeping at night. Some people can drink a cup of coffee right before bed and have no trouble getting to sleep. Others would be wired. I think it probably varies from person to person. I did notice a caffeine-type "buzz" for the first day or two when I began taking selegeline, but nothing now. One more thing, I take .25mg alprazolam (Xanax) at night before bed. This is half a pill at the lowest dosage. It helps me sleep through the night but doesn't make me feel drugged in the morning. I was having trouble waking up many times between 3:00 and 6:00 a.m. before taking this. No problems now. Hope this helps. Keith Chancey 45/1 Memphis, TN