I had Gamma Knife on 4/18/06. At the facility I went to, they give you a little white pill, I suppose so that you don't decide to bolt and run at the last minute, or get anxious about being in the headframe and being phasered. This little white pill (Xanax, I think) does it's job quite well. The whole experience, for me now, is kind of like I was kidnapped by aliens and taken aboard the mother ship for medical testing and then let go, with a muddled memory of what happened, and a lot of missing time!! That afternoon I slept like a baby, or the dead, because I didn't hear the phone ringing beside me, or anything for about 4 hours, I think. I'm kind of sorry I was drugged up so much, because the experience was kind of interesting, and I was looking forward to taking it all in. But, maybe, if they give you a pill, you won't react as I did. But the nurse told us, "She will not remember some of the things going on here this morning."..so I guess that's what this pill does to you. On the billing we got, that pill cost $168.00. I hope you read this before you leave for your treatment, because, honestly, it was very painless and stress-free...because of the meds. If you are put on steroids, be aware that a common side effect is insomnia. Get a couple of good movies or books...because you may be awake at 3 a.m and wondering what to do. That was the worst of the whole thing and I was soooo glad when I finally could sleep. You'll be fine.