Amantadine

Medically Reviewed by Dr. Harshi Dhingra, M.D.

Last Reviewed: Mar 23, 2023

Side Effects


Amantadine Side Effects

Possible side effects of amantadine are listed below. Call your doctor for medical advice if these side effects are severe or if they do not go away in a few days.

  • Dry mouth
  • Constipation
  • Nausea
  • Vomiting
  • Decreased appetite
  • Sleep difficulties
  • Unusual dreams
  • Confusion
  • Headache
  • Drowsiness
  • Fatigue
  • Falls, changes in walking patterns, or unusual muscle tightening
  • Purple lace-like patterns on the skin

Some of the adverse effects of amantadine can be more serious. Call your doctor right away or seek emergency medical help if you experience:

  • Hallucinations (seeing or hearing things that are not there)
  • Paranoia (feeling like others want to hurt you)
  • Delusions (believing things that are not true)
  • Depression and anxiety
  • Lack of interest in usual activities
  • Suicidal thoughts or behavior (thoughts about harming or killing yourself or planning or trying to do so)
  • Blurred vision, dizziness, fainting
  • Swelling of the hands, lower legs, ankles, or feet
  • Shortness of breath
  • Urinary retention

The above list may not include all the potential side effects of amantadine. Contact your healthcare provider if your side effects are unusual or severe or they do not get better over time. You can also report unusual side effects to the Food and Drug Administration at 1-800-FDA-1088.

Amantadine Overdose: In case of an overdose of amantadine, call your doctor immediately. You can also call the national poison control center at 1-800-222-1222. Call 911 if a person has collapsed, cannot be awakened, has trouble breathing, or has had a seizure. Symptoms of an amantadine overdose may include difficulty breathing, fast or irregular heartbeat, stiff muscles in the arms or legs, fatigue, swelling of the hands or feet, decreased urination, uncontrolled shaking or movements in the body, confusion, poor coordination, aggressive behavior, irritability, and hallucinations.

Source: FDA