Linda, some people never need it and I almost got away without it. Didn't give in until the last week of rad when the neck burns really began to get the upper hand. If I knew then what I know now, I would have asked for it about a week before. You should have a free pass for the first couple of weeks at least, and probably longer. I am not sure there is a norm, as it depends on skin type, where the rad is aimed, what kind of rad, and whether there is concurrent chemo. You are very correct in that each of us reacts differently. I managed on just OTC Tylenol for almost the entire time. In fact, I always took a Tylenol about 30 min. prior to treatment because that table was so hard. Also, the patches did not make me at all sleepy or nutso, and I was up to 3 at one point post-treatment. Just remember, it is your right as a patient, not to hurt. Being in pain hinders healing. I found the gearing up phase almost endless, but once treatment began, it went rather quickly. Actually, because of the kind people on this forum 4 years ago, I was prepared for much worse than I experienced. While I was waiting for the other shoe to drop, for things to get REALLY ugly, I was done! I hope this is your experience also.