Some people do very well on drug therapy, and it's not likely their doctors will want to take them off in order to experiment, especially since it has been shown that going off the medications, and then returning to them, can sometimes lose ground for the patient.
Read the complete post at http://www.mindingoureldersblogs.com/2008/07/lighting-may-increase-quality-of-life-for-people-with-alzheimers.html