Parkinson's Disease

[pdmech73]

i need a little help with understanding the treatment of parkinson's disease. am i on the dot with both explainations? i am not sure i explained the rationale for drug holiday and the physiology of the on-off phenomenon of pd thoroughly. if not, please let me know. i just want to make sure i'm on point with each explaination.

thanks,

-paul :-)

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what is the rationale for placing parkinson's disease patients on a drug holiday after long term treatment?

my explaination:

[color=#333333][color=#333333][color=#333333]long-term administration of levodopa is the most effective drug therapy for parkinson’s disease. however, there are limitations and side effects of levodopa such as the on-off phenomenon, dyskinesias, and dsyrhythmias. after an extended period of continuous usage, some patients may even experience that levodopa is no longer as effective. long-term use of levodopa may also further induce neurodegeneration of dopaminergic neurons. therefore, temporary withdrawal from levodopa, or a drug holiday, has been promoted as a way to manage complications of long-term levodopa therapy. a drug holiday is a brief interruption of drug use during a variable of time in hopes of permitting the drug to regain effectiveness and reduce adverse side effects & the body’s tolerance to the drug.

with long term levodopa treatment, what is the physiology behind the on-again/off-again" appearance of symptoms that happen?

my explaination:

[color=#333333][color=#333333]the on-again/off-again phenomenon occurs in some patients that have taken levodopa for an extended period of time in which the duration of effectiveness of each dose gradually decreases such that the patient alternates from a good response to the drug to no response. because of the consistent intake of levodopa to prevent off-periods, levodopa has been shown to overload the brain with neurotoxic breakdown products resulting from the oxidation of dopamine. patients can experience periods where they have great control (on time) of their movements while having a good response to levodopa and a period where they have they poor control (off time). off time, or breakthrough pd, is the period in which the patient has little or no response to levodopa. they can encounter abrupt changes in muscle tones switching from rigidity (off), to a normal dyskinetic state (on), and back to cogwheel rigidity within seconds or minutes. these fluctuations of motor control are also believed to be caused by the number of years levodopa has been taken in addition to the further progression of the disease in the brain and postsynaptic alterations of the striatum.

[Tharem]

Sounds great except in the second paragraph, line 10 has an extra 'they', in line thirteen 'tones' should be changed to 'tone' followed by a comma, and in line seventeen there should be a comma after 'brain'. Hope this helps.