Brief Answer:
Clozapine, seroquel, and pimavanserin are all very effective

Detailed Answer:
Hi there,

Parkinson disease is a progressive neurodegenerative disorder caused by degeneration of dopaminergic neurons. Cardinal symptoms include resting tremor, rigidity, bradykinesia or slow movements, and postural instability. It is the second most common neurodegenerative disease after Alzheimer disease.

Levodopa combined with carbidopa is still the most effective treatment for symptoms of Parkinson disease since it increases the amount of dopamine in the brain and domaine pathways.

Was zyprexa not working anymore? Or was it worsening your parkinson's disease?

What dose of seroquel were you taking?

Clozapine and seroquel do not appear to worsen parkinsonism as do other atypical neuroleptics, and therefore, they are generally recommended. However, clozapine can cause serious blood count issues and requires weekly blood draws so it is only used in very serious cases of psychosis that are resistant to other medications. Therefore, Clozapine is underutilized because of the nuisance of hematologic monitoring, but it is probably the most effective of the atypical neuroleptics in this setting.

Since seroquel is easier to use than clozapine (no monitoring required) and often effective, it should be the treatment of first choice.

The antipsychotic agent pimavanserin was effective for reducing PD-related psychosis is a recent small trial. Treatment was well-tolerated and was not associated with worsening of motor symptoms or other adverse effects. This drug is likely to be used widely, given its novel mechanisms of action and the limitations posed by other antipsychotics. However, the long-term safety and efficacy of pimavanserin has not been established.

I hope this helps. Let me know if you have additional questions.

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