Forest Labs will be discontinuing the sale of Namenda (recommended dose is 10 mg. twice daily) in August. At that time, I will have to switch my mother from Namenda to Namenda XR which is a once-daily formulation of 28 mg. I am concerned with the possibility of side effects with the higher daily dose. Should I be concerned? Forest Labs has informed that the two dosages are comparable. But how do they know since they were tested head-to-head in clinical trials? So, I remain skeptical.