There are currently two classes of medications that are FDA approved for treating Alzheimer’s disease. The cholinesterase inhibitors have been in use the longest. There are three drugs in this class Aricept (generic name is donepezil and it is now available in generic equivalent form), Exelon (generic name is rivastigmine and is available as either an oral tablet or as a patch), and Razadyne (generic name is galantamine). In general, despite conflicting opinions of efficacy and mechanism of action, drugs from this class tend to increase the level of acetylcholine in neurons and slow the rate of progression in many who can tolerate them. These medications are FDA approved for all stages of Alzheimer’s disease. There is no clear clinical benefit for one over another.

The other medication is named Namenda (other brand names are Axura, Akatinol, Ebixa, or Memox and the generic name of memantine). This medication is in a class called NMDA receptor antagonists and works by blocking the neurotransmitter known as glutamine (although it also affects serotonin, dopamine, and acetylcholine). Namenda was approved by the FDA in 2003 for moderate to severe Alzheimer’s disease and is usually used in combination with one of the cholinesterase inhibitors. There is evidence that use of one of the cholinesterase inhibitors together with Namenda is more effective in moderate to severe Alzheimer’s disease than using either medication alone.

Over the years, there has been widespread “off label” use of Namenda for those with either Mild Cognitive Impairment or Mild Alzheimer’s disease. Indeed, a recent survey indicated that 63% of those with these diagnoses are on Namenda and 40% of neurologists prescribe Namenda for early stage cases. The dilemma is that there is lack of evidence for the use of Namenda for early Alzheimer’s disease let alone Mild Cognitive Impairment.

A new analysis has been recently published reviewing treatment outcomes for Namenda in about 450 patients with mild and about 700 patients with Moderate Alzheimer’s disease. There were no statistically significant differences between treatment with Namenda versus placebo for mild cases. There was a significant effect for treatment with Namenda for those with moderate Alzheimer’s disease.

The bottom line is that Namenda has no proven efficacy for those with Mild Cognitive Impairment or Mild Alzheimer’s disease. Of course, the number of studies is quite limited. However, as a consumer, one needs to decide whether or not to take this medication for early stages of cognitive decline. These decisions need to be based on outcome from clinical trials as well as cost-benefit ratios. First, Namenda is expensive. A 30 day supply costs about $130 – $200 per month. Second, Namenda has potential side effects including confusion, dizziness, drowsiness, headache, insomnia, agitation, and/or hallucinations. The decision to use Namenda for mild decline is between you and your physician but weigh the trade-offs before deciding.