I think that depends on how much improvement you are seeing with each treatment.  If the Fraxel settings are good you should be getting about 15-20% coverage with each treatment so at five treatments, you would be approaching 80-90% coverage since there is some overlap each time.   You may be reaching close to maximal effects.  I just don't want you to continue to spend money and not see much improvement.   If you still think you need improvement, I would allow at least a 3 month period from the last Fraxel for maximum collagen generation.  Also consider changing to a fractionated CO2 laser, especially if you are over 40.  Dr. I