Amantadine
Purpose of Medication and Method of Action
Amantadine is indicated for the prevention and treatment of influenza infections due to the influenza A virus. It is also indicated in the treatment of Parkinson's disease. The mechanism of action in preventing flu is unknown but may be by preventing the replication of the virus within human cells. For Parkinson's disease it may act by stimulating the release of dopamine, the deficiency of which is thought to be one of the basic causes of Parkinson's disease.
Side Effects
The most common side effects are: nausea, dizziness, and insomnia which are seen in 5-10% of those taking this medication. Other less frequent reactions include: depression, hallucinations, dry mouth, low blood pressure on arising, and dream abnormalities.
Drug Interactions
Co-administration with thioridazine (Mellaril) may worsen the tremor of Parkinson's disease. When taken with the combination of hydrochlorthiazide (HCTZ) and amantadine the blood levels of amantadine may increase with a subsequent increase of side effects.
Cautions and Contraindications
Patients with a history of seizures may experience an increased incidence of seizures. Amantadine should not be discontinued abruptly in patients taking for Parkinson's disease.
Usual Dose
Influenza prophylaxis and treatment: 200 mg daily as one dose. Parkinson's disease - 100 mg (1 tablet) two times a day increasing to a maximum of 400 mg daily in divided doses.
Patient Medication Information
These information sheets do not list all known side effects of the medications, only the most common side effects. For a complete list of side effects please contact your local pharmacy or the actual drug manufacturing company.