Drug information of Amantadine

Amantadine

Drug group:

Amantadine is an antiviral medication. It blocks the actions of viruses in your body. Amantadine is used to treat and to prevent influenza A (a viral infection). There may be some flu seasons during which amantadine is not recommended because certain flu strains may be resistant to this drug. Amantadine is also used to treat Parkinson's disease and "Parkinson-like" symptoms such as stiffness and shaking that may be caused by the use of certain drugs.

Mechanism of effect

Antiviral The mechanism by which Amantadine exerts its antiviral activity is not clearly understood. It appears to mainly prevent the release of infectious viral nucleic acid into the host cell by interfering with the function of the transmembrane domain of the viral M2 protein. In certain cases, Amantadine is also known to prevent virus assembly during virus replication. It does not appear to interfere with the immunogenicity of inactivated influenza A virus vaccine.

Pharmacodynamic

Amantadine is an antiviral drug which also acts as an antiparkinson agent

Pharmacokinetics

Amantadine hydrochloride is well absorbed orally. Approximately 67% bound to plasma proteins over a concentration range of 0.1 to 2.0 µg/mL. No appreciable metabolism, although negligible amounts of an acetyl metabolite have been identified. It is primarily excreted unchanged in the urine by glomerular filtration and tubular secretion. Mean half-lives ranged from 10 to 14 hours.

Dosage

Usual Adult Dose for Influenza A Normally recommended dose: 200 mg orally per day in 1 to 2 divided doses Usual Adult Dose for Parkinson's Disease Monotherapy: 100 mg orally twice a day; onset usually within 48 hours In patients with serious associated medical illnesses or receiving high doses of other antiparkinson drugs: Initial dose: 100 mg once a day After 1 to several weeks at initial dose: The dose may be increased to 100 mg orally twice a day, if needed. Usual Adult Dose for Extrapyramidal Reaction 100 mg orally twice a day

Alerts

1- Patients with a history of epilepsy or other "seizures" should be observed closely for possible increased seizure activity. 2- Suicide attempts, some of which have been fatal, have been reported in patients treated with Amantadine, 3- Amantadine Hydrochloride should not be discontinued abruptly in patients with Parkinson's disease since a few patients have experienced a parkinsonian crisi

Points of recommendation

1-Blurry vision and/or impaired mental acuity may occur. 2-Avoid excessive alcohol usage, since it may increase the potential for CNS effects such as dizziness, confusion, lightheadedness and orthostatic hypotension. 3-Notify physician if mood/mental changes, swelling of extremities, difficulty urinating and/or shortness of breath occur. 4-Consult physician before discontinuing medication

Pregnancy level

C


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