Medications to Treat Dementia

Approximately 75% of all cases of dementia are caused by Alzheimer’s Disease or vascular brain disease, or by a combination of both disorders. Medications are now available that have been effective in improving mental function in persons with Alzheimer’s Disease, vascular dementia, and with mixed Alzheimer’s and vascular dementia. These medications are also being used more frequently to treat a condition known as Mild Cognitive Impairment (MCI). None of these medications stop the progression of cognitive decline, but they appear to slow down the rate at which such decline occurs. This can help ease the burden of family caregivers and delay placement in a long term care facility.

What medications are currently being prescribed?

There are two classes of medications currently being prescribed to treat Alzheimer’s Dementia: “Cholinesterase Inhibitors” such as Aricept (Donepezil), Exelon (Rivastigmine), and Razadyne (Galantamine); and an “NMDA Receptor Antagonist”, Namenda (Memantine).

How do these medications work?

Cholinesterase Inhibitors: Acetylcholine is a substance manufactured by nerve cells in the brain. It helps transmit “messages” between cells, allowing a person to think and perform tasks. Alzheimer’s Disease and vascular brain disease both destroy some of the brain cells that make acetylcholine. Cholinesterase inhibitors temporarily boost the levels of acetylcholine in the brain, thereby preserving memory and cognitive function.

NMDA Receptor Antagonists regulate the activity of glutamate, another “messenger” chemical in the brain. Glutamate triggers NMDA receptors in the brain to allow a controlled amount of calcium to flow into nerve cells to help the brain process, store and retrieve information. Excess amounts of glutamate cause NMDA receptors to allow too much calcium into nerve cells, leading to disruption and death of cells. Namenda may protect cells against excess glutamate by partially blocking the NMDA receptors.

What can I expect these medications to do for my loved one?

Cholinesterase Inhibitors: From 30%-50% of those taking cholinesterase inhibitors experience a mild but noticeable improvement in attention, concentration and in the ability to perform daily activities. The average improvement was comparable to “rolling back” the disease symptoms anywhere from 6-12 months. Cholinesterase Inhibitors appear to be most effective in the early to middle stages of dementia. NMDA Receptor Antagonists:  In US clinical studies, Memantine has proven modestly effective in improving functional performance in persons with moderate to late-stage dementia. It may be most effective when used along with a cholinesterase inhibitor.

What should be considered when using these medications?

Dementia medications differ in two main areas: the number of daily doses required and the types of potential side effects. Aricept and the extended release form of Razadyne tablets are taken once daily. Exelon and Namenda are taken twice daily. Exelon is also available in a once-a-day patch.

The most common side effects of Aricept, Exelon and Razadyne are nausea, vomiting, loss of appetite and diarrhea. The most common side effects of Namenda are dizziness, headache and constipation. When they occur, these symptoms tend to be mild and transient in nature. Side effects may be prevented by starting out with the smallest possible dose of medication, then gradually increasing it to the highest dose. When side effects do appear, they may be able to be overcome by reducing the dose for a week or so, and then increasing it again. These medications may not be appropriate for persons with certain medical conditions. Your physician can determine whether a person has any medical conditions or potential risk factors that would preclude them using these medications.        

As a rule of thumb, if a person is taking one of these medications - and is doing well - they should not switch to another. If they are not doing well on a particular medication (ie. having side effects, or showing no benefit after 6 months of use), it would be reasonable to stop that drug and to then start another, either in the same or a different class. If a person cannot take, or does not benefit from, any of these currently prescribed medications, it would be reasonable to consider enrolling them in a clinical research trial for medications that are still being tested.

What do these medications cost?

The current cost for a one-month’s supply of Aricept, Exelon, Razadyne or Namenda is approximately $180. Generic forms of these medications may be available at a lesser cost. These medications are covered by many of the Medicare-approved prescription drug plans. The pharmaceutical companies that produce these medications may also offer them free or at a discount to persons of limited means, and without insurance coverage for medications. Speak to your physician or pharmacist about these Patient Assistance Programs, or go online to the following sites:  Benefits
Checkup:   http://www.benefitscheckup.org/  or Partnership for Prescription Assistance:  www.pparx.org

How do I obtain a prescription for these medications?

Any medical doctor may prescribe them. However, it is essential that an accurate diagnosis for the cause of cognitive problems be made first. To do this, the physician must perform a thorough physical examination, blood tests and a brain scan. The physician should also administer basic cognitive tests, and should review all the medication the person currently takes to look for possible side effects. Finally, the physician should gather from the family a detailed history of the type of onset and progression of the cognitive and functional decline, and the type of symptoms they have observed. Such a thorough evaluation will help the physician identify and treat other medical conditions that may be mistaken for Alzheimer’s or vascular brain disease.

What about medications that are currently being tested?

Clinical research studies are part of a careful, scientific process to see whether new treatment approaches are safe and effective. After first being tested in the laboratory, and then with animals, treatments that appear promising are then tested on humans in carefully designed clinical trials.

Interested persons are first screened to see if they are candidates to participate in a clinical trial. Those selected for a trial will be divided into two groups: one group will receive the trial medication and another will receive a “placebo”, a pill with no active medication in it. Patients agree to a series of follow-up appointments and phone calls to track their progress – or any side effects - over time. The medications, physical and cognitive examinations and lab tests are provided free of charge. For information about clinical trials in the Omaha area, contact the UNMC Psychopharmacology Research Consortium at 402-552-6005.

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