About Alzheimer's medications
Alzheimer's medications include drugs in several categories that may help some of the symptoms of Alzheimer's disease and some other forms of dementia. At this time, there is no cure for Alzheimer's disease, nor is there any method to slow the progression of the disease. However, there are treatment options available that can minimize or stabilize patients’ symptoms and in some cases delay the necessity of nursing home care.
Alzheimer's disease is a disease of the brain that gets worse over time. It is the most common cause of dementia among people over the age of 65, according to the National Institute of Neurological Disorders and Stroke (NINDS). Alzheimer's disease is not a normal sign of aging. Little is understood about what causes Alzheimer's disease and what can be done to prevent or cure it. The symptoms of Alzheimer's disease occur when neurons (nerve cells) in the brain die or break their connections with other neurons.
The symptoms of Alzheimer's disease generally fall into two categories: cognitive (e.g., dementia, memory loss, language loss) and psychiatric (e.g., behavioral problems, hallucinations). Physicians may prescribe medication to treat each of these symptoms separately.
There are two main types of medications that are used to treat the cognitive symptoms of Alzheimer's disease: cholinesterase inhibitors and N-methyl D-aspartate receptor antagonists (NMDAs).
Cholinesterase inhibitors work by maintaining the levels of a chemical called acetylcholine in the brain. Acetylcholine is a neurotransmitter, which means that it carries electrical signals from one neuron to another. This chemical is essential for memory, judgment and learning. In people with Alzheimer's disease, the cells that produce acetylcholine are damaged or killed and levels of the chemical gradually decline in the brain. This leads to a loss in cognitive function.
Cholinesterase inhibitors work to delay the breakdown of acetylcholine and keep the levels high enough for the brain to function normally. However, cholinesterase inhibitors cannot stop the progressive nature of cell damage and, eventually, the damage from the disease will develop to the extent that it is too severe for cholinesterase inhibitors to be effective.
The other type of medication used to treat the cognitive symptoms of Alzheimer's disease is NMDA receptor antagonists. These drugs work by regulating the amount of another neurotransmitter called glutamate. Glutamate is also important for memory and learning. However, if there is too much glutamate in the brain, it can overstimulate parts of the brain and cause the disruption and death of neurons. Currently, the only NMDA receptor antagonist approved by the Food and Drug Administration (FDA) is memantine (Namenda).
Medications are also used to treat the psychiatric symptoms of Alzheimer's disease. These medications include antidepressant medications to treat depression and low moods, anti-anxiety medications to treat anxiety or verbally disruptive behavior and antipsychotic medication to treat hallucinations, delusions or aggression.
Additionally, trials are taking place to test the effectiveness of anticonvulsants and statin therapy to treat Alzheimer's disease. Statins are commonly used to treat high cholesterol levels but are also believed to have a positive effect against mild to moderate forms of dementia.
Types and differences of Alzheimer's medications
People who are diagnosed with Alzheimer's disease may require different types of medication to treat the various symptoms of the disease. Some medications are designed to treat the cognitive symptoms (e.g., memory loss, language loss) and others are designed to treat psychiatric symptoms (e.g., behavioral problems, hallucinations).
Medications used to treat cognitive symptoms include:
These work by maintaining the levels of acetylcholine, a neurotransmitter in the brain. Like all medications for treatment of Alzheimer's disease, cholinesterase inhibitors cannot stop the progression of the disease and, eventually, the damage to the brain will be too severe for cholinesterase inhibitors to be effective. The three most commonly prescribed cholinesterase inhibitors are:
- Donepezil (Aricept)
- Rivastigmine (Exelon)
- Galantamine (Reminyl, Razadyne)
NMDA receptor antagonists
This type of medication works by regulating the amount of another neurotransmitter called glutamate. Currently, the only NMDA receptor antagonist approved by the Food and Drug Administration (FDA) is memantine (Namenda).
The psychiatric symptoms of Alzheimer's disease are often treated with medication aimed to reduce depression, anxiety, hallucinations or delusions. However, these medications may produce more severe side effects in patients with dementia, which includes most Alzheimer's patients. Additionally, some psychiatric medications have not been tested for their effectiveness in patients with Alzheimer's disease. Medications that may be prescribed for patients with behavioral or psychiatric symptoms include:
Antidepressants are medications used to treat major depression and many other conditions (e.g., personality disorders, anxiety disorders). They appear to work by increasing the levels of one or more neurotransmitters serotonin, norepinephrine and dopamine in the brain. Commonly prescribed antidepressants include sertraline, fluoxetine, escitalopram and trazodone.
Anti-anxiety medications are drugs most often used to relieve symptoms of fear and anxiety experienced by some people. They are highly effective in treating most types of anxiety disorders, regardless of the underlying cause, and some may begin to work in as little as 30 to 90 minutes. Commonly prescribed anti-anxiety medications include diazepam, chlordiazepoxide, flurazepam and estazolam.
Antipsychotics are medications used mainly to treat psychosis, a severe mental condition in which a patient loses touch with reality. They do not cure the condition, but help control symptoms such as hallucinations and delusions. Commonly prescribed antipsychotic medications for the symptoms of Alzheimer's disease include risperidone, quetiapine, olanzapine and clozapine.
In addition to medication that has been approved by the Food and Drug Administration (FDA), some companies market herbal remedies and supplements as alternative treatment methods for Alzheimer's disease. These remedies may be sold as dietary or herbal supplements, which are not subject to the same FDA approval process as drugs. Supplements need only prove they are safe and cannot make specific health claims. For example, some supplements may say they aid memory, rather than help Alzheimer's disease.
Some alternative treatments include:
- Coenzyme Q10 (ubiquinone). An antioxidant that occurs naturally in the body. Antioxidants reduce the amount of oxidative stress caused by free radicals. People with Alzheimer's disease may have low levels of coenzyme Q10 and some claims suggest that supplements of coenzyme Q10 may slow the progress of Alzheimer's disease. However, these claims have not been substantiated.
- Ginkgo biloba. An herb that is claimed by some to improve memory. It also acts as an antioxidant and has been used for hundreds of years to treat a number of medical conditions related to oxidative stress. Although it is not regulated by the FDA, ginkgo biloba is used in traditional Chinese medicine, as a prescription drug in parts of Europe and is one of the most popular herbal supplements in the United States. The National Center for Complementary and Alternative Medicine (NCCAM) is conducting a long-term study on the use of ginkgo biloba for memory improvement in healthy elderly people.
- Huperzine A. A dietary supplement that may function similarly to a mild cholinesterase inhibitor. Huperzine A is derived from the Chinese cub moss plant. Studies have not been completed to establish the safety of its use in people with Alzheimer's disease.
- Phosphatidylserine. A type of lipid (fat) that may protect nerve cells from degenerating. Scientists are unsure how phosphatidylserine works, although it is thought to work in a similar way to cholinesterase inhibitors.
It is important to discuss the use of alternative treatment methods with a physician before purchasing or taking these products. Some alternative remedies could interact with prescribed medication or lead to more serious health complaints. Ginkgo biloba, for example, can cause bleeding in some people and may increase the risk of complications in people with diabetes.
Conditions of concern
Patients should consult with their physician about taking Alzheimer’s medications if they have been diagnosed with any of the following conditions:
- Kidney disease
- Heart disease
- Lung disease
- Repeated urinary tract infections
- Enlarged prostate gland
- Side effects
Potential side effects
In general, Alzheimer’s medication can be taken with little impact on daily life. In fact, Alzheimer’s medication may help people who are experiencing debilitating symptoms of Alzheimer's disease to live a more normal life.
Most Alzheimer’s medications make the patient drowsy, especially when the course is first started. This may make it dangerous to drive a vehicle or operate machinery required for work. Alcohol often adds to the drowsiness, so patients may be advised to stop drinking alcohol.
Common side effects of Alzheimer’s medications, including those used to treat psychiatric problems, include:
- Gastrointestinal problems (upset stomach, vomiting, diarrhea)
- Loss of appetite
- Abnormal dreams
- Difficulty falling asleep or staying asleep
- Runny nose
Some Alzheimer’s medications may have more severe symptoms, which could include:
- Pain while urinating
- Blood in urine, stool or vomit
- Vomiting material that looks like coffee grounds
- Slowed heartbeat
Patients who experience any of the above severe symptoms while taking Alzheimer’s medication should consult a physician immediately.
Tobacco may interfere with the effectiveness of cholinesterase inhibitors and NMDA receptor antagonists (e.g., memantine). Therefore, people on these medications should quit smoking tobacco. Nicotine products used to quit smoking may also affect the medications. A physician may be consulted if the patient needs help to quit smoking.
Drug or other interactions
Patients should consult their physicians before taking any additional prescriptions, over-the-counter medications, nutritional supplements or herbal medications. Of particular concern to individuals taking Alzheimer’s medications are:
- Aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs). Some types of NSAIDs such as aspirin or ibuprofen may interact with Alzheimer’s medications.
- Other Alzheimer's disease medications. Most Alzheimer's medications interact with other drugs used to treat the condition. In general, Alzheimer's disease should not be treated with more than one type of medication. This is also true of medications used to treat psychiatric symptoms.
- Anticholinergics. Medications for spasms commonly used to treat symptoms of Parkinson's disease and in some surgical procedures. They may interact with many drugs used to treat Alzheimer’s disease. Patients are advised to discuss the use of anticholinergics and Alzheimer’s medications with a physician.
- Other interactions. Some other drug interactions, which may reduce the effectiveness of medication or cause adverse side effects, include:
- Donepezil with anticonvulsants, such as carbamazepine and phenobarbital
- Vitamin E with anticoagulants (medications used to stop blood from clotting)
- Memantine with antacids, such as cimetidine
- Galantamine with certain antibiotics, such as erythromycin
- How to use
Alzheimer's disease is rarely diagnosed in women of childbearing age. However, a rare form of Alzheimer's disease called early-onset Alzheimer's disease may sometimes affect people as in their 20s and 30s.
Women who are pregnant or are planning to become pregnant should consult with their physician about any medication used to treat Alzheimer's disease.
Elderly use issues
Most Alzheimer's patients are elderly and are more likely to have concerns with all medications. Alzheimer’s medications may not pass as quickly through the bodies of elderly patients as they do younger patients. As a result, elderly people may be especially likely to experience certain side effects associated with Alzheimer’s medications, including gastrointestinal problems and loss of weight.
Additionally, elderly people are more likely to be taking other medications that may interact with Alzheimer’s medication or have conditions that may affect the potency or side effects of Alzheimer’s medications. This is especially the case if the patients have conditions such as kidney, lung or heart disease.
Symptoms of medication overdose
Patients or caregivers of patients exhibiting any of these symptoms should contact their physicians immediately:
- Loss of consciousness
Questions for your doctorPatients or caregivers may wish to ask their doctor the following questions about Alzheimer’s medications:
- Should I be taking medication to control the symptoms of my Alzheimer's disease?
- Which Alzheimer’s medications should I be taking?
- To what extent will this medication control my Alzheimer's disease?
- What should I do if I forget to take my medication?
- What should I do if I experience any side effects from my medication?
- Are there any over-the-counter medications I should avoid while taking Alzheimer’s medication?
- How will you know when to increase the dose of my medication?
- Will I have to take my Alzheimer’s medication forever?
- Are there any herbal remedies that could also help to control my Alzheimer's disease?
- How closely should I monitor a parent taking medications for Alzheimer's disease?
- Will the medications become less effective over time?