Parkinsonโ€™s disease

Active Ingredient: Amantadine

Indication for Amantadine

Population group: only adults (18 years old or older)

Amantadine is indicated for Parkinson’s disease.

For this indication, competent medicine agencies globally authorize below treatments:

100 mg daily for one week and thereafter 200 mg in two divided doses

Dosage regimens

Oral, 100 milligrams amantadine, daily, over the duration of 1 week. Afterwards, oral, 200 milligrams amantadine, divided 2 times daily. The maximum allowed total dose is 400 milligrams amantadine daily.

Detailed description

Initially 100 mg daily for the first week, increasing to 100 mg twice daily. The dose can be titrated against signs and symptoms. Doses exceeding 200 mg daily may provide some additional relief, but may also be associated with increasing toxicity. A dose of 400 mg/day should not be exceeded. The dose should be increased gradually, at intervals of not less than 1 week.

Adults over 65 years of age: Since patients over 65 years of age tend to show lower renal clearance and consequently higher plasma concentrations, the lowest effective dose should be used.

Amantadine acts within a few days, but may appear to lose efficacy within a few months of continuous treatment. Its effectiveness may be prolonged by withdrawal for three to four weeks, which seems to restore activity. During this time, existing concomitant antiparkinsonian therapy should be continued, or low dose L-dopa treatment initiated if clinically necessary.


Amantadine withdrawal should be gradual, e.g. half the dose at weekly intervals. Abrupt discontinuation may exacerbate Parkinsonism, regardless of the patient’s response to therapy.

Combined treatment

Any antiparkinson drug already in use should be continued during initial amantadine treatment. It may then be possible to reduce the other drug gradually. If increased side effects occur, the dosage should be reduced more quickly. In patients receiving large doses of anticholinergic agents or L-dopa, the initial phase of amantadine treatment should be extended to 15 days.

Active ingredient


Amantadine has been shown to be a low affinity antagonist at the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors. Overactivity of glutamatergic neurotransmission has been implicated in the generation of parkinsonian symptoms. In addition, amantadine specifically inhibits the replication of influenza A viruses at low concentrations.

Read more about Amantadine

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