My mother took Namenda 5 mg and seemed to do well, however, she became mean and uncooperative.. The only thing that had changed was the dosage of Namenda had been increased from 5 mg to 10 mg. When we decreased the Namenda back to 5 mg, my father said it was like night and day. She was cooperative again. Now the psych doctor insists on increasing her Namenda dosage and she is mean and mostly uncooperative. The psych doc said it is probably because her dementia is progressing. Anyone have any similar experience with a loved one and Namenda?