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Medications

It has been known for some time that those suffering from Alzheimer’s disease have low levels of acetylcholine (an important brain chemical involved in nerve cell communication).

shutterstock_3140438.jpgCholinesterase inhibitors slow the metabolic breakdown of acetylcholine, and make more of this brain chemical available for communication between cells. This helps slow the progression of cognitive impairment and can be effective for some patients in the early- to middle-stages of Alzheimer’s disease. Recent studies concerning one of the medications in this category, Aricept®, have shown that it can also be helpful for managing symptoms in patients with severe Alzheimer’s disease. There are five medicines approved by the FDA:

 

Razadyne® (formerly Reminyl®) (Generic name: galantamine)

Year Approved by the FDA: 2001

Effective for: Early to moderate Alzheimer’s disease

How it works: Razadyne® prevents the breakdown of acetylcholine and stimulates nicotinic receptors to release more acetylcholine in the brain.

Most common side effects: Nausea, vomiting, diarrhea, weight loss

 

Exelon® (Generic name: rivastigmine)

Year Approved by the FDA: 2000

Effective for: Early to moderate Alzheimer’s disease

How it works: Exelon® prevents the breakdown of acetylcholine and butyrylcholine (a chemical similar to acetylcholine) in the brain.

Most common side effects: Nausea, vomiting, weight loss, upset stomach, weakness

 

Aricept® (Generic name: donepezil)

Year Approved by the FDA: 1996

Effective for: Early, moderate and severe Alzheimer’s disease

How it works: Aricept® prevents the breakdown of acetylcholine in the brain.

Most common side effects: Nausea, diarrhea, vomiting

Miscellaneous: According to information released by the Mayo Clinic and the National Institute on Aging, Aricept also appears to have a slowing effect—though limited—on the progression from mild cognitive impairment to Alzheimer's disease. The study was published in the April, 2005 edition of the New England Journal of Medicine. The patients in the study had the memory-related variety of mild cognitive impairment, a transitional stage between the forgetfulness of normal aging and the more serious memory decline and other problems associated with Alzheimer's disease. Over the first year of the three-year trial, mild cognitive impairment patients treated with Aricept had a reduced risk of progressing to Alzheimer's diseas compared to patients who took a placebo, an inactive pill. The study found the effect of the Aricept treatment lasted longer (up to two to three years) in those patients carrying the ApoE4 gene. Previous studies have shown those with the ApoE4 gene have a higher propensity to develop Alzheimer's diseas than the general population.

 

Cognex® (Generic name: tacrine)

Year Approved by the FDA: 1993 (Cognex is still available but no longer actively marketed by the manufacturer, due to the severe side effects.)

Effective for: Early to moderate Alzheimer’s disease

How it works: Cognex prevents the breakdown of acetylcholine in the brain.

Most common side effects: Nausea, diarrhea, possible liver damage

 

Namenda® (Generic name: Memantine HCL)

Year Approved by the FDA: 2003

Effective for: Early, moderate and severe Alzheimer’s disease

How it works: Glutamate is a chemical in the brain that has been associated with learning and memory. Abnormal glutamate activity in the brain may lead to Alzheimer's disease symptoms. Namenda may help improve normal glutamate activity. This is believed to be important for learning and memory

Most common side effects: Dizziness, constipation, headache and confusion

Miscellaneous: Combination Alzheimer's therapy – adding Namenda (memantine HCl) to another Alzheimer's medicine – has been shown to do more to fight the effects of Alzheimer's disease than taking Aricept (donepezil) alone.

How is this possible? The answer may lie in the unique way Namenda works.Nerve cells rely on a variety of chemical messengers to transmit messages from one cell to the next. One of those chemical messengers is called glutamate, another is called acetylcholine.

In Alzheimer's, the processes involving both of these chemical messengers are affected, though in different ways. A different problem exists with acetylcholine – there may be too little acetylcholine in the brain of a person with Alzheimer's. Acetylcholinesterase inhibitors, also called AChEIs, Alzheimer's medications like Aricept (donepezil), Razadyne (galantamine), and Exelon (rivastigmine) work by addressing that problem.

Since Namenda and AChEIs target different aspects of Alzheimer's disease, it makes sense that they can work well together and do more when used in combination to slow the progressive symptoms of Alzheimer's disease.

 

A thoughtful evaluation must be performed by a physician before taking any medications, over-the-counter drugs, supplements, or herbs. The American Health Assistance Foundation does not endorse any of these medications, vitamins, or herbs. A qualified physician should make an informed decision based on each person's medical history and current prescriptions. The medication summaries provided do not include all of the information important for patient use and should not be used as a substitute for professional medical advice. The prescribing physician should be consulted concerning any questions that you have.

The information provided in this section of our website was obtained from the National Institute on Aging, the Mayo Clinic,Clinical Trials.gov and the National Institute of Health