Drugs for Alzheimer’s disease and Side Effects

Abstract

The main available medications approved by FDA to treat Alzheimer’s disease are – Donepezil, Galantamine, Rivastigmine, Memantine and Namzaric, a combination memantine and donepezil (Fig. 1-5), which belong to drugs called “cholinesterase inhibitors”. They prevent the breakdown of acetylcholine, a chemical messenger significant for learning, memory, thinking, language, judgment and other thought processes. Cholinesterase inhibitors increase levels of acetylcholine. Some brain cells produce acetylcholine, which helps deliver messages to other cells. When a message reaches the receptor cell, various other chemicals, including acetylcholinesterase enzyme, break down acetylcholine. Alzheimer’s disease destroys or demages cells that produce and use acetylcholine. Thus, acetylcholineesterase inhibitors block the activity of ecetylcholinesterase enzyme, but these inhibitors can’t reverse Alzheimer’s and do not stop the gradual destruction of nerve cells and their ability to improve symptoms eventually declines as brain cell damage progresses. F. e. galantamine stimulate the release of acetylcholine, rivastigmine block the activity of another enzyme involved in acetylcholine breaking down. These two drugs are approved to treat mild to moderate Alzheimer’s, but donepezil is used for treating all stages of the Azlheimer’s disease. Memantine improves memory, attention, reason, language and ability to do simple tasks. It is used to treat moderate to severe Alzheimer’s, as it regulates the activity of glutamate, a chemical involved in information processing. There are many side effects include headache, constipation, confusion, dizziness, loss of appetite, increased frequency of bowel movements, nausea, vomiting etc.