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At 10:19 PM 8/3/97 -0400, you wrote: >Does anyone have any knowledge of amentadine including side affects? > >[log in to unmask] > > Amantadine. Patients less than 6O years of age. Amantadine is an antiviral agent discovered by chance to have antiparkinson activity.Its principal mechanism of action has not been established, but it is known to increase dopamine release, block dopamine reuptake, stimulate dopamine receptors, and-based on its clinical effects-to have peripheral anticholinergic properties.In uncontrolled studios, two thirds of patients receiving amantadine monotherapy showed improvement in akinesia, rigidity, and tremor.Amantadine appears to be more effective than anticholinergic drugs with regard to akinesia and rigidity but is less effective with regard to tremor. Placebo-controlled studies have confirmed improvement in all of the cardinal manifestations of PD. Benefit from amantadine is transient in some patients, with one third of patients showing reduced benefit within 4 to 8 weeks of initiation of treatment. In some studies, however, the benefit has been sustained for as long as 1 year. Amantadine is best used as short-term monotherapy for a period of 6 to 12 months in the treatment of patients with mild to moderate parkinsonism. Response frequently correlates with response to levodopa, making it particularly suitable for use before levodopa. If its effect wanes and other antiparkinsonian medications are added, amantadine should be discontinued to avoid unnecessary polypharmacy. Gradual withdrawal is recommended to prevent acute exacerbation of parkinsonian symptoms. Amantadine provides either modest or no significant additional benefit when added to levodopa treatment. Addition of levodopa to amantadine treatment however, produces a significant improvement. Amantadine has a plasma half-life of 10 to 28.5 hours and can be administered twice daily in dosages of 100 to 300 mg daily. Larger dosages provide no additional benefit and increase the likelihood of adverse effects. This drug's major advantage is a <bold>low incidence of side effects</bold> but, since it is excreted largely unchanged in the urine, it should be used with caution in patients with renal failure. Peripheral vascular side effects include livedo reticularis and ankle edema, but these are rarely severe enough to limit treatment. Confusion, hallucinations, insomnia, and nightmares can occur but are less common in patients aged 60 years or less, and they are more likely to occur when amantadine is used in combination with other antiparkinsonian drugs. Dry mouth and blurred vision are presumed to be peripheral anticholinergic side effects, but they seem to occur more commonly when amantadine is given in combination with anticholinergic drugs. In summary, amantadine is indicated for early treatment of PD in patients 60 years of age or less who have mild akinesia and rigidity and in whom tremor is not a major problem. Its therapeutic effects are relatively mild and might be limited in duration, but its low potential for side effects makes it particularly useful for early administration. Patients greater than 60 years of age. Amantadine may be used as early monotherapy for patients over age 60 with the same guidelines as for patients under aged 60 and under. Since the use of anticholinergic drugs is discouraged in this age group (discussion to follow), amantadine fills the need for a mild antiparkinsonian drug with low risk for adverse cognitive effects. Nonetheless, the risk for cognitive impairment with amantadine use is greater at this age, and appropriate caution should be exercised In patients older than 60 years of age, an initial dose of 100 mg once daily should be administered for 1 week before increasing to 100 mg bid. Doses higher than 200 mg daily are discouraged in this age=20 group =A0see more: http://neuro-chief-e.mgh.harvard.edu/parkinsonsweb/Main/ Drugs/ManPark1.html HP