Parkinson's disease is a slowly progressive disease: the cause is still unknown.
The symptoms can range from tremor, rigidity, bradykinesia, postural instability
and autonomic dysfunction to cognitive disturbances. The pathophysiological
mechanism for most of these symptoms is the degeneration of the
nigrostriatal tract, leading to a shortage of dopamine in the striatum.
Levodopa given orally, can be an effective drug for most of these symptoms,
but not all symptoms respond equally. In addition, the progression of the
disease continues in spite of levodopa treatment. Longterm levodopa treatment
can lead to considerable side-effects.
In the early phases of the disease amantadine and anti-cholinergics are to be
preferred above levodopa. However, anticholinergics do have a reputation of
side-effects with regard to cognitive function, since acetylcholine is an
important neurotransmitter for systems involved in memory functions