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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: amantadine (a MAN ta deen)
Brand name(s): GOCOVRI, OSMOLEX
GENERIC: available FAMILIES: Drugs for Viral Infection, Drugs for Parkinson’s Disease
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

This drug caused harm to developing fetuses in animal studies, including malformations and death. Because of the potential for serious adverse effects to the fetus, this drug should not be used by pregnant women.

Breast-feeding Warning

Amantadine is excreted in human milk. Because of the potential for serious adverse effects in nursing infants, you should not take this drug while nursing.

Facts About This Drug [top]

Amantadine is approved by the FDA to prevent and treat influenza A, Parkinson’s disease, and drug-induced movement disorders.[1] If you are over 60, you will probably need to take less than the usual adult dose. For use against flu, a lower dose of no more than 100 milligrams is recommended for older people, even less if your kidney function is impaired or you are underweight.[2],[3]

For flu (influenza) prevention, it is best to get a flu shot early in the season. However, if you cannot...

Amantadine is approved by the FDA to prevent and treat influenza A, Parkinson’s disease, and drug-induced movement disorders.[1] If you are over 60, you will probably need to take less than the usual adult dose. For use against flu, a lower dose of no more than 100 milligrams is recommended for older people, even less if your kidney function is impaired or you are underweight.[2],[3]

For flu (influenza) prevention, it is best to get a flu shot early in the season. However, if you cannot get a flu shot because it is unavailable, or you have a medical condition that prevents it, you can use amantadine. During outbreaks of the flu, amantadine may be prescribed in addition to earlier flu shots. For amantadine to be effective against the flu, you must take it within 48 hours of your first flu symptoms.[4]

Your doctor may also prescribe amantadine if you have Parkinson’s disease, usually as a supplement to another drug. A combination of two drugs called levodopa and carbidopa (SINEMET, SINEMET CR) is the best treatment for Parkinson’s disease. Amantadine is often effective only for a limited time (less than six months), and it often produces adverse effects such as confusion, lightheadedness, hallucinations, and anxiety, which reduce its usefulness.[5] When you are taking amantadine, especially if you are a woman, the skin of your legs may become mottled (this is known as livedo reticularis). This will go away when you stop taking the drug.

If you have symptoms of parkinsonism, you should know that they might be caused by a drug that you are taking for another problem. As many as half of older adults with these symptoms may have developed them as an adverse effect of one of their drugs. See list of drugs that can cause symptoms of parkinsonism. If you are taking any of the drugs on this list, discuss the possibility of drug-induced parkinsonism with your doctor and ask to have your prescription changed or stopped.

Deaths have been reported from overdose with amantadine (Symmetrel). The lowest reported acute lethal dose was 1 gram. Immediate, short-term adverse effects may be attributable to the anticholinergic affects of amantadine.[6]

Before You Use This Drug [top]

Tell your doctor if you have or have had:

  • allergy to amantadine
  • blood vessel disease of the brain
  • congestive heart failure
  • eczema (recurring)
  • heart disease
  • swelling of feet and ankles
  • kidney disease
  • mental illness or substance abuse
  • seizures, epilepsy
  • stomach ulcers
  • pregnancy or are breast-feeding

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Check with your doctor if there is no improvement within a few days.
  • Until you know how you react to this drug, do not drive or perform other activities requiring alertness. Amantadine can cause fainting, confusion, or impaired vision.
  • Check with your doctor immediately if thoughts of suicide occur.
  • You may feel dizzy when rising from a lying or sitting position. If you are lying down, hang your legs over the side of the bed for a few minutes, then get up slowly. When getting up from a chair, stay by the chair until you are sure that you are not dizzy.
  • Do not drink alcohol.
  • If you get dry mouth, use sugarless candy or gum, ice, or saliva substitute. Check with your doctor or dentist if this lasts more than two weeks.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Space doses evenly.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Take this drug for the prescribed length of time. If you stop too soon, your symptoms could come back.
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.

Interactions with Other Drugs [top]

Evaluations of Drug Interactions 2003 lists no drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods as causing “highly clinically significant” or “clinically significant” interactions when used together with the drugs in this section. We also found no interactions in the drugs’ FDA-approved professional package inserts. However, as the number of new drugs approved for marketing increases and as more experience is gained with these drugs over time, new interactions may be discovered.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • confusion or hallucinations
  • depression
  • thoughts of or attempts at suicide
  • severe mood or mental changes
  • difficulty urinating
  • fainting
  • slurred speech
  • memory loss
  • increased blood pressure
  • uncontrolled rolling of eyes
  • fever, chills, or sore throat
  • swelling of feet or lower legs
  • shortness of breath
  • rapid weight gain
  • skin rash
  • vision changes
  • lack of coordination
  • irritation and swelling of the eye

Call your doctor if these symptoms continue:

  • difficulty concentrating
  • dizziness or lightheadedness
  • diarrhea
  • irritability
  • loss of appetite
  • nausea or vomiting
  • agitation, anxiety, or nervousness
  • red, blotchy spots on skin
  • nightmares
  • trouble sleeping
  • constipation
  • dry mouth, nose, and throat
  • headache
  • unusual tiredness or weakness
  • decreased sexual ability

Signs of overdose:

  • shortness of breath
  • heart rate changes
  • aggressive behavior
  • agitation
  • anxiety
  • stumbling
  • coma
  • confusion
  • delirium
  • disorientation
  • fear
  • hallucinations
  • trouble sleeping
  • lethargy
  • hypertension
  • fever
  • seizures

If you suspect an overdose, call this number to contact your poison control center: (800) 222-1222.

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • monitoring for an increase in seizures (if you have or have had epilepsy or seizures)

last reviewed April 30, 2021