Medications Used in Treatment of Alzheimer’s Disease
Five prescriptions have been approved by the Food and Drug Administration (FDA) to treat those who have been diagnosed with Alzheimer’s disease. Although there is still no cure for Alzheimer’s, these medications can provide patients with comfort, dignity and independence for a longer period of time. This can also can encourage and assist caregivers.
The following medications are used to treat mild to moderate Alzheimer’s disease. They are called cholinesterase inhibitors. They help delay or prevent symptoms from becoming worse for only a limited time. They may also help some behavioral symptoms.
Razadyne (galantamine) was formerly known as Reminyl. It is extracted from the bulb of certain types of daffodils. Although it is generally well tolerated is does have some gastrointestinal side effects that include nausea, diarrhea, weight loss, dizziness and headaches. Less common side effects include sleeplessness, confusion and slow heartbeat. The side effects are more common when taking higher doses.
There is a major concern relating to Razadyne. In two clinical trials it was indicated that those taking Razadyne had a higher death rate than those taking a placebo. Fifteen people taking part in the drug trials died from a number of conditions including heart attack and strokes. This was compared to only five deaths from those taking the placebo pills. The drug information now includes this warning.
Exelon (rivastigmine) has significant stomach-related side effects that include nausea, vomiting, loss of appetite and weight loss. Side effects occur more frequently as the doses are increased. During clinical trials Exelon and placebos were compared. They both had a wide range of responses, but Exelon groups were showed to be more likely to have greater improvements.
Aricept (donepezil) is usually well tolerated, but it is not for everyone. Side effects include nausea, diarrhea, sleeplessness and vomiting, muscle cramps, tiredness, loss of appetite or fainting.
Cognex (tacrine) is no longer actively marketed by the manufacturer. Side effects include abdominal pain, abnormal pain, abnormal thinking, agitation, anxiety, chest pain, clumsiness or unsteadiness, confusion, constipation, coughing, depression, diarrhea, dizziness, fatigue, flushing, frequent urination, gas, headache, inflamed nasal passages, insomnia, indigestion, liver function disorders, rash, sleepiness, upper respiratory infection, urinary tract infection, vomiting and weight loss. Less common side effects include back pain, hallucinations, hostile attitude, purple or red spots on skin, skin discoloration and tremors and weakness.
Scientists don’t fully understand how cholinesterase inhibitors treat Alzheimer’s disease. Research indicates they prevent the breakdown of Acetylcholine. This is a brain chemical that is believed to be important for memory and thinking. As Alzheimer’s progresses the brain produces less and less Acetylcholine, therefore cholinesterase inhibitors may eventually lose effect.
No study compares these drugs. They all work in similar ways. It is not believed that switching from one drug to another will not produce significant changes although it is possible for an Alzheimer’s patient may respond to one drug better than another.
The fifth medication is Namenda (memanitine) is used to treat moderate to severe Alzheimer’s disease. This medicine is a methyl D-aspartate (NMDA) antagonist. The main effect of this medicine is to delay progression of some symptoms. This may allow patients to maintain certain daily functions a little longer, such as the ability to go to the bathroom independently for several months more. Namenda is believed to work by regulating glutamate, a brain chemical that when produced in excessive amounts may lead to brain cell death.
Methyl D-aspartate and cholinesterase inhibitors work completely different from each other. They can be used in combinations with each other to better treat Alzheimer’s disease.
