Amantadine: Medication for Fatigue Treatment in Multiple Sclerosis

Medication May Also Prevent Influenza, Relieve Parkinson's Disease

Amantadine is a prescription medication that may be used to treat fatigue in multiple sclerosis (MS)
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Amantadine, previously sold under the brand name of Symmetrel in the United States, is a prescription medication that is used for the treatment of fatigue in multiple sclerosis (MS). How does amantadine work? What are some of the more common and serious side effects? Learn about this medication and how it might help reduce fatigue as a medication treatment in multiple sclerosis.

Uses of Amantadine for Neurological Diseases

Amantadine may be used to prevent infection with the influenza A virus, a cause of the common flu. It also can be used to treat symptoms associated with Parkinson’s disease and relieves the side effects of antipsychotic medications (so-called extrapyramidal side effects). In addition, amantadine has been found to be helpful in reducing symptoms of fatigue among people with multiple sclerosis.

How Does Amantadine Work to Improve Fatigue?

The way that amantadine works in such distinct conditions is not fully understood. It is believed to block the influenza virus as it attempts to remove its outer coat and release the nucleic acid that is used to take over the host cell, ultimately interfering with the replication of the virus. The mechanisms for its effect in Parkinson’s disease, as well as how it may address fatigue in MS, are unknown. But it is believed that it may potentiate the responses to the neurotransmitter called dopamine in the central nervous system.

Who Should Not Use Amantadine?

In order to avoid unwanted side effects, it is important that the use of amantadine not be suddenly stopped. In addition, there are a number of situations where the medication should be used with caution or not at all. In particular, its use should be carefully considered in the elderly, those with depression or other psychiatric problems, and in some chronic health conditions, including: congestive heart failure, cardiovascular disease, peripheral edema, glaucoma, and seizures. In addition, people with kidney or liver impairment may need to use amantadine cautiously. Finally, its use should be avoided in high environmental temperatures due to the potential effects of dehydration.

What Are Common Side Effects of Amantadine?

As with every drug, there is a risk of side effects with the use of amantadine. Although many people do not experience any side effects, some that commonly occur with the use of amantadine include:

  • Depression
  • Anxiety
  • Hallucinations
  • Confusion
  • Insomnia
  • Somnolence
  • Abnormal dreams
  • Compulsive behaviors
  • Irritability
  • Dizziness
  • Orthostatic hypotension (lightheadedness with standing)
  • Headache
  • Dry mouth (xerostomia)
  • Loss of appetite (anorexia)
  • Nausea
  • Diarrhea
  • Constipation
  • Swelling in feet (Peripheral edema)
  • Clumsiness (ataxia)
  • Livedo reticularis (skin condition)

What Are Potential Serious Reactions to Amantadine?

As with the use of most drugs, there is also the risk of serious side effects when using amantadine. These more serious reactions occur infrequently. With the use of amantadine, some of the potential serious reactions include:

  • Suicidal thoughts
  • Psychosis
  • Coma
  • Seizures
  • Impaired vision
  • Oculogyric crisis (abnormal eye movements)
  • Congestive heart failure (CHF)
  • Arrhythmias (abnormal heart rhythms)
  • Cardiac arrest
  • Respiratory failure
  • Pulmonary edema
  • Anaphylaxis
  • Abnormal blood counts (agranulocytosis, neutropenia, leukopenia)
  • Heat stroke
  • Neuroleptic malignant syndrome (with abrupt cessation)

What Safety Precautions and Monitoring Should Occur with Amantadine?

As described above, some people should not use amantadine or should use it only with caution. In addition, it is important that amantadine not be abruptly discontinued. This could potentially cause serious side effects. The safety of the medication’s use in pregnancy and lactation is not well established and should probably be avoided. When the medication is started, a measurement of kidney function called creatinine should be assessed via blood draw. While being taken, regular skin examinations should occur to check for side effects.

If you experience any difficulties with the use of amantadine, you should be in close contact with your prescribing health provider.

A Word From Verywell

Amantadine can be an effective treatment for fatigue caused by multiple sclerosis, symptoms associated with Parkinson’s disease, and in preventing the common flu. Elderly individuals, those dealing with psychiatric problems, and those with chronic health conditions should use caution or abstain from taking amantadine. Make sure to talk with your physician about the common side effects and serious reactions that can occur in taking this medication. While taking this medication, be sure to receive regular checkupsU.S. Food and Drug Administration. "Symmetrel (Amantadine Hydrochloride) Syrup and Tablets." Silver Springs, Maryland; updated January 2009.. Remember: abrupt discontinuation of the medication is not advised.

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Article Sources

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  • U.S. Food and Drug Administration. "Symmetrel (Amantadine Hydrochloride) Syrup and Tablets." Silver Springs, Maryland; updated January 2009.

  • “Amantadine.” Epocrates Rx Pro. Version 13.9,1, 2013. Epocrates, Inc. San Mateo, California.