Generic Amantadine

Common use

Amantadine is an antiviral and antiparkinsonian medication used to treat Parkinson’s disease, drug-induced extrapyramidal symptoms, and certain viral infections like influenza A. It works by influencing dopamine activity in the brain and interfering with viral replication. In Parkinson’s disease, it helps reduce tremors, stiffness, and movement difficulties. As an antiviral, it is used mainly for prophylaxis and early treatment of specific flu strains.

Dosage and direction

The usual adult dose ranges from 100 mg to 200 mg per day, depending on the condition being treated. It is typically taken once or twice daily, with or without food. Swallow the tablet or capsule whole with water, and try to take it at the same time each day. Dosage adjustments may be necessary for elderly patients or those with kidney impairment.

Precautions

Before using amantadine, inform your doctor if you have kidney disease, seizure disorders, heart failure, hypotension, or a history of mental health issues. It may cause drowsiness, dizziness, or blurred vision, so avoid driving or operating machinery until you know how it affects you. Use caution in the elderly, as they may be more sensitive to CNS effects like confusion or hallucinations. Do not stop taking the medication suddenly without consulting your doctor.

Contraindications

Amantadine is contraindicated in individuals with known hypersensitivity to the drug. It should be avoided in patients with untreated angle-closure glaucoma. Use with caution in those with severe renal impairment, unless the dose is properly adjusted. It is not typically recommended for children unless prescribed specifically.

Possible side effect

Common side effects include nausea, dry mouth, dizziness, insomnia, and loss of appetite. Some patients may experience swelling in the legs, skin mottling (livedo reticularis), or nervousness. More serious but rare effects include hallucinations, confusion, or orthostatic hypotension. Report any unusual mood changes, visual disturbances, or difficulty urinating to your doctor.

Drug interaction

Amantadine may interact with anticholinergic drugs, CNS stimulants, diuretics, and other Parkinson’s medications like levodopa. Combining with alcohol or other sedatives can enhance drowsiness. Caution is advised when taken with medications that affect kidney function or cause CNS side effects. Always inform your healthcare provider of all drugs and supplements you are taking.

Missed dose

If you miss a dose, take it as soon as you remember unless it's close to the time for your next dose. Do not take two doses at once. Resume your regular schedule afterward. Missing doses may reduce the effectiveness of the treatment.

Overdose

An overdose of amantadine can cause serious symptoms like hallucinations, irregular heartbeat, agitation, seizures, or coma. Immediate medical attention is necessary if an overdose is suspected. Supportive treatment and monitoring in a hospital may be required. There is no specific antidote for amantadine overdose.

Storage

Store amantadine at room temperature (20°C to 25°C / 68°F to 77°F), away from light and moisture. Keep the container tightly closed and out of reach of children. Do not use expired medication. Ask your pharmacist how to properly dispose of unused or expired medicine.

Disclaimer

We provide only general information about medications which does not cover all directions, possible drug integrations, or precautions. Information at the site cannot be used for self-treatment and self-diagnosis. Any specific instructions for a particular patient should be agreed with your health care adviser or doctor in charge of the case. We disclaim reliability of this information and mistakes it could contain. We are not responsible for any direct, indirect, special or other indirect damage as a result of any use of the information on this site and also for consequences of self-treatment.

Clinical Verification

Last Clinically Updated: August 15, 2026

Written By

Dr. Elena Vance, PharmD

Clinical Specialist in Neuropharmacology

Fact Checked By

Marcus Thorne, MS

Biomedical Data & FDA Label Verification

Medically Reviewed By

Dr. Arthur Campbell, MD

Board-Certified Psychiatrist (ABPN)