Amantadine is used to alleviate the symptoms of fatigue in multiple sclerosis. It is an antiviral medication which improves muscle control and reduces muscle stiffness. Amantadine is also used for patients with Parkinson's disease due to its efficacy in treating muscle stiffness and loss of muscle control - both of which are potential symptoms of MS. As with many drugs, the effectiveness of Amantadine in dealing with MS fatigue was a chance discovery that came about when a number of people with MS were being treated for 'flu using its anti-viral properties. The anti-viral properties may confer other benefits because viral infections have been shown to be significantly correlated with relapses.
Amantadine inhibits viral replication by interfering with the influenza A membrane protein, M2. Amantadine treatment of established influenza A infection does not appear to interfere with antibody response to the infection. Because prophylactic use of amantadine can prevent influenza illness and to a less extent subclinical infection, some patients who take amantadine for prophylaxis can still develop immune response to infections. Amantadine has little or no activity against influenza B or against parainfluenza at concentrations that inhibit influenza A. Frequently, resistance to amantadine can develop in strains of influenza A exposed to low concentrations the drug. Immunocompromised patients receiving amantadine who shed virus for longer than 3 days tend to have resistant viruses. Amantadine is well absorbed from the GI tract.
Amantadine is a medication used to treat and prevent infection with influenza (flu) viruses. It also is effective in treating some symptoms of Parkinson's disease, although it is not clear how it works. Amantadine may cause greater amounts of dopamine to be released in the brain, and it may lower levels of acetylcholine, a brain chemical that contributes to movement. Amantadine is a synthetic (man-made) anti-viral drug that can inhibit the replication of viruses in cells. To prevent a viral infection, the drug should be present before exposure to the virus. Clearly, this is not practical for most viral infections. It was initially used to prevent influenza A during flu season, and, if given within 24 to 48 hours of the onset of flu symptoms, to decrease the severity of the flu. Later amantadine was found to cause improvement in the symptoms of Parkinson's disease. Amantadine's mechanism of action in Parkinson's disease is not fully understood. Its effects may be related to its ability to augment (amplify) the effects of dopamine, a neurotransmitter in the brain, that is reduced in Parkinson's disease. Amantadine is less effective than levodopa in Parkinson's disease but can offer additional benefit when taken with levodopa.