Tablets, syrup
To prevent or treat type A influenza; to treat Parkinson's disease. It may also be used to minimize stiffness and shaking caused by certain other drugs prescribed for treating nervous, mental, or emotional disorders.
The exact mechanism of action is unknown, though amantadine appears to prevent the influenza A virus from penetrating and entering healthy cells. In Parkinsonism, it increases the release and activity of dopamine, which plays a key role in the control of muscle movement. The increased availability of dopamine in the brain helps compensate for the reduction in the natural supply caused by the disease, and so eases symptoms of Parkinsonism.
For treatment or prevention of influenza-- Adults: 100 to 200 mg a day in one or two doses for five days. Children: Up to 150 mg once a day. For Parkinsonism-- Adults: 100 mg, two times a day. In some cases the maximum dose may be increased to 400 mg a day. Older patients and those with a history of seizure disorders are usually given reduced doses, generally 100 mg a day.
For influenza A: two hours. For Parkinsonism: 48 hours.
Up to 12 hours.
Take it with or after meals.
Store in a tightly sealed container away from heat and direct light.
If you miss a dose, take it as soon as you remember unless it is almost time for your next dose. In that case, skip the missed dose and return to your regular schedule. Do not double the next dose.
Influenza: For prevention, take amantadine for the full treatment period as recommended by your doctor; for treatment, do not stop taking amantadine without consulting your doctor. Parkinsonism: Doses must be decreased gradually according to your doctor's instructions.
Prolonged use requires periodic checks by your doctor.
Older persons are generally more sensitive to amantadine and more likely to experience adverse side effects. Smaller doses may be warranted.
Amantadine can cause drowsiness, dizziness, blurred vision, or confusion. Avoid driving and hazardous work until you determine how the medicine affects you.
Avoid alcohol since it may increase side effects such as dizziness and blurred vision.
In some animal studies, amantadine has been shown to cause birth defects, though human studies have not been done. Accordingly, the drug should be avoided during the first three months of pregnancy. Notify your doctor if you are pregnant or plan to become pregnant.
Amantadine passes into breast milk and should not be taken while breast feeding.
Safety for children under the age of one has not been established.
Individuals with kidney disease must take reduced dosages and be closely monitored.
Hyperactivity, disorientation, confusion, visual hallucinations, seizures, drop in blood pressure, palpitations or heart rhythm disturbances.
Call your doctor, emergency medical services (EMS), or the nearest poison control center immediately.
The effects of amantadine can be altered by amphetamines, diet pills, asthma and cold medicines, methylphenidate, nabilone, and pemoline. Anticholinergic drugs can increase the side effects of amantadine.
None are expected.
Caution is advised when taking this medication. Consult your doctor if you have eczema, epilepsy, heart disease, circulation problems, kidney disease, or an emotional disorder.