About 5 percent of people between the ages of 65 and 74 and half of people older than 85 have Alzheimer's disease, making it the most common type of dementia, according to the Mayo Clinic. People afflicted with Alzheimer's disease gradually lose critical thought processes, memory and normal social skills. There is no cure for Alzheimer's disease, but some medications can slow the progress of the disease and others can control some of the symptoms.
Cholinesterase Inhibitors
A class of drugs called cholinesterase inhibitors slows the progression of Alzheimer's disease by increasing the level of a neurotransmitter in the brain that functions in memory and judgment. People with Alzheimer's disease have too little of the brain chemical acetylcholine. Donepezil (Aricept), galantamine (Razadyne) and rivastigmine (Exelon) bind to the enzyme acetylcholinesterase so that it cannot degrade acetylcholine. With more acetylcholine available, the function of cholinergic neurons that serve in memory and cognitive function improves.
Common side effects of these medications include vomiting, nausea and diarrhea. The side effects occur more frequently in women and peak during the first weeks of drug use. Your doctor might prescribe donezepil first because it is taken only once per day and tends to be well-tolerated. Galantamine might work best for behavioral symptoms. If symptoms don't improve within a few months of starting to take a cholinesterase inhibitor, you should stop taking the drug.
Memantine
An excess of the amino acid glutamate in the brains of people with Alzheimer's disease overstimulates neurons and can kill brain cells. The drug memantine (Nemanda) can slow the progression of Alzheimer's disease by dialing down the function of glutamate receptors so that glutamate cannot overstimulate brain cells. According to the Mayo Clinic, combination therapy of memantine with a cholinesterase inhibitor might have better effects than either drug alone. However, people with kidney disease should take very low doses or avoid it altogether because of problems with excreting the drug. Dizziness, confusion and headache are the most common side effects of memantine.
SSRIs
In addition to cognitive difficulties, people with Alzheimer's often struggle with anxiety, depression, and behavioral problems. Medications such as sedatives and anti-depressants can help to treat these symptoms. For depression, people with Alzheimer's should not take anticholinergic drugs because they would worsen cognitive symptoms, but selective serotonin re-uptake inhibitors (SSRIs) might be a good choice. Because of the possibility of drug interactions, you must tell your doctor about all of the medications that you take.
