The drugs memantine and donepezil when taken together do not interfere with each other's ability to treat Alzheimer's disease patients, according to a study presented at the American Medical Director's Association in Orlando, Fla.

Forest Laboratories is seeking approval from the U.S. Food and Drug Administration to market mematine for the treatment of moderate-to-severe Alzheimer's disease. Donepezil, whose brand name is Aricept, is already approved for this purpose.

In their study of 24 healthy patients, researchers found that memantine and donepezil when taken together do not interfere with each other's absorption, metabolism, distribution or elimination. Additionally, memantine did not significantly alter the inhibition of red blood cell acetylcholinesterase activity produced by donepezil alone.

Memantine, an N-methyl-D-aspartate (NMDA) receptor, is the first of a new class of medications for Alzheimer's disease with a mechanism of action distinct from currently available drugs. Memantine may block the effects associated with excessive transmission of glutamate, which is thought to be responsible for brain cell death seen in Alzheimer's disease.

Other sources: Forest Laboratories