Rivastigmine
Definition
Rivastigmine is a drug used to treat symptoms of Alzheimer's disease. In the United States, rivastigmine is sold as the brand name drug Exelon.
Purpose
Rivastigmine is used to treat symptoms of Alzeheimer's disease in individuals with mild to moderate illness. It has also been used to treat dementia caused by other conditions such as Lewy-body disease or following strokes. The drug may produce mild improvements in symptoms of thinking for a short period of time, but rivastigmine does not cure or stop progression of underlying diseases.
Description
The Food and Drug Administration approved rivastigmine in 2000 specifically for treating Alzheimer's disease. In Alzheimer's disease, some cells in specific regions of the brain die. Because of this cell death, these brain cells lose their ability to transmit nerve impulses. Brain cells normally transmit nerve impulses another by secreting various chemicals known as neurotransmitters.
Brain cells that make and secrete a neurotransmitter called acetylcholine are affected early in the course of Alzheimer's disease. Rivastigmine prevents the breakdown of acetylcholine in the brain, thus temporarily increasing its concentration. In doing so, rivastigmine may improve the thinking process by facilitating nerve impulse transmission within the brain.
Rivastigmine is available as capsules in four different strengths and as an oral solution for use by people who have difficulty swallowing. Unlike some other drugs used to treat Alzheimer's disease, the liver does not break down rivastigmine. As a result, it may be preferred in the treatment of people with Alzeheimer's disease who have liver disease.
Recommended dosage
The initial dosage of rivastigmine is 1.5 mg taken two times per day. If this dose is tolerated without difficulty, the dosage may be increased to 3 mg twice a day after at least two weeks at the lower dosage. Some people are unable to tolerate nausea, vomiting, anorexia, and weight loss that occur with higher dosages. If the drug does not cause significant adverse effects, the dose may be increased to 4.5 mg two times per day, followed by 6 mg two times per day. The dosage should be increased slowly, at two-week intervals. If side effects occur and cannot be tolerated, the drug may be stopped for several doses. When the drug is started again, the same dosage or the next lower dosage may be tried. The maximum daily dosage is 6 mg two times per day.
