Memantine, commonly prescribed in the United States under the brand name Namenda, is for people with moderate-to-severe Alzheimer’s disease and vascular dementia. It isn’t a cure (there is no cure for Alzheimer’s or related dementias) but studies have shown memantine treats symptoms by improving memory, awareness, and concentration.
Available as pill to be taken daily, memantine enhances “neuron synaptic plasticity,” which is a technical way of saying that it improves communication between brain cells, making it easier for the brain to change and learn, improving a person’s ability to perform the normal daily tasks made too challenging by dementia’s impact on the brain.
Severe restlessness has also been shown to be relieved for people who take memantine. Nighttime can be especially difficult for someone with dementia (and for caregivers trying to keep that someone safe) and memantine’s effect on the brain is demonstrated to make nights more calm.
Namenda was approved by the FDA in 2003 and is available as a tablet, a solution, and an extended-release capsule.
Numerous studies have demonstrated its effectiveness for people with mid- to late-stage Alzheimer’s disease. In clinical trials, memantine out-performed a placebo for patients in these phases of the disease. (It did not work for someone in the early stages of dementia.) What scientists found was that subjects studied while taking the medicine still saw a deterioration of their ability to perform daily tasks like brushing teeth or getting dressed, but the deterioration was slower. For mental performance, things like learning and remembering, it was the same: Subjects still got worse but at a slower rate.
Interestingly, studies have also analyzed whether caregivers saw improvement in their own mental states. Taking care of a loved one with Alzheimer’s is difficult and extremely stressful. Unfortunately, this burden was not relieved despite moderate improvement in the sick individuals being cared for.
Signals communicated across brain cells essentially enable us to think, learn, and remember. A neurotransmitter called glutamate helps this process by carrying the signals across cells, but patients with Alzheimer’s have too much glutamate, and the excess throws the process awry, damaging the cells, even killing them, and muddling the message. Memantine prevents excess glutamate from killing cells, without damaging the signal.
Memantine is different from a cholinesterase inhibitor, which is another kind of medicine prescribed for persons with Alzheimer’s or other dementia (typically in earlier stages). Cholinesterase inhibitors also work to increase communication between cells but target a different neurotransmitter. Memantine and cholinesterase inhibitors, in fact, can be prescribed together, and studies have shown they may work in tandem to ease symptoms.
Memantine has been reported in studies as being well-tolerated, with few side effects. That said, watch for fatigue, aches, dizziness, nausea, and constipation.
The important (much rarer) side effects, which caregivers should watch for because of how memantine impacts signals in the brain, are shortness of breath and hallucinations. If either of these are observed, contact a doctor immediately or seek emergency services.
Medicare Part D, which covers prescription drugs, and Medicare Advantage, which is tailored through a private insurer to fit the specific patient, should both cover the cost of Namenda (or generic equivalent) if it is prescribed by a doctor.