
Parkinson’s Disease Related Psychosis
By Nicklesh Thakur, D.O., Sutter Medical Group
Hallucinations and delusions are typically thought to be associated with illnesses like schizophrenia, but are also a frequent complication of Parkinson’s disease (PD). It is estimated that psychosis will affect over 50% of people with PD and is more common with longer duration of disease, dementia, and older age. There is a variety of symptoms seen in psychosis and is triggered by medications (dopaminergic, narcotics, benzodiazepines, etc.), underlying infections or metabolic disturbances (delirium) or dementia.
Hallucinations involve a person seeing or hearing something that is actually not there. Visual hallucinations are most common in PD, which can involve seeing people or animals while awake during the day, evening, or at night. Delusions are false beliefs or illogical views that are not based in reality, which typically involves accusing spousal infidelity or fear of being poisoned. Other symptoms of psychosis include illusions (mistaking an object for something else) or false sense of presence (feeling someone is close by when no one is there).
The initial step in diagnosing the cause of PD psychosis involves ruling out other conditions like infections (pneumonia or UTI) or metabolic disturbance (electrolyte imbalance). If testing is negative, then PD medications must be adjusted since psychosis can occur as a side effect. Medication reduction or elimination will usually improve the psychosis, but may lead to worsening motor symptoms. We will then have to use antipsychotic medications, which are typically used for mood disorders like schizophrenia by blocking dopamine receptors. They are considered off-label therapies for PD psychosis and may also worsen motor symptoms due to dopamine blockade. Clozapine (clozaril) and quetiapine (seroquel) are atypical antipsychotics that are most commonly used since they are less likely to make motor symptoms worse. The limitations to quetiapine includes minimal efficacy seen in research trials and side effects of sleepiness. In comparison, Clozapine is highly effective, but has a rare life threatening side effect called agranulocytosis (the drug attacks the bone marrow), so it is rarely used due to weekly blood monitoring.
On April 29, 2016, Pimavanserin (Nuplazid) was the first medication approved by the FDA for PD psychosis. Pimavanserin has a novel mechanism of action by acting on the serotonin receptors instead of dopamine, so it improves psychosis and does not worsen motor symptoms like the antipsychotics. It has also been shown to improve nighttime sleep, daytime wakefulness, and reduction in caregiver burden. Pimavanserin is an exciting new therapy since PD psychosis often
leads to loss of independence, increase in caregiver burden, and nursing home placement.
Parkinson Path JULY 2016
By Nicklesh Thakur, D.O., Sutter Medical Group
Hallucinations and delusions are typically thought to be associated with illnesses like schizophrenia, but are also a frequent complication of Parkinson’s disease (PD). It is estimated that psychosis will affect over 50% of people with PD and is more common with longer duration of disease, dementia, and older age. There is a variety of symptoms seen in psychosis and is triggered by medications (dopaminergic, narcotics, benzodiazepines, etc.), underlying infections or metabolic disturbances (delirium) or dementia.
Hallucinations involve a person seeing or hearing something that is actually not there. Visual hallucinations are most common in PD, which can involve seeing people or animals while awake during the day, evening, or at night. Delusions are false beliefs or illogical views that are not based in reality, which typically involves accusing spousal infidelity or fear of being poisoned. Other symptoms of psychosis include illusions (mistaking an object for something else) or false sense of presence (feeling someone is close by when no one is there).
The initial step in diagnosing the cause of PD psychosis involves ruling out other conditions like infections (pneumonia or UTI) or metabolic disturbance (electrolyte imbalance). If testing is negative, then PD medications must be adjusted since psychosis can occur as a side effect. Medication reduction or elimination will usually improve the psychosis, but may lead to worsening motor symptoms. We will then have to use antipsychotic medications, which are typically used for mood disorders like schizophrenia by blocking dopamine receptors. They are considered off-label therapies for PD psychosis and may also worsen motor symptoms due to dopamine blockade. Clozapine (clozaril) and quetiapine (seroquel) are atypical antipsychotics that are most commonly used since they are less likely to make motor symptoms worse. The limitations to quetiapine includes minimal efficacy seen in research trials and side effects of sleepiness. In comparison, Clozapine is highly effective, but has a rare life threatening side effect called agranulocytosis (the drug attacks the bone marrow), so it is rarely used due to weekly blood monitoring.
On April 29, 2016, Pimavanserin (Nuplazid) was the first medication approved by the FDA for PD psychosis. Pimavanserin has a novel mechanism of action by acting on the serotonin receptors instead of dopamine, so it improves psychosis and does not worsen motor symptoms like the antipsychotics. It has also been shown to improve nighttime sleep, daytime wakefulness, and reduction in caregiver burden. Pimavanserin is an exciting new therapy since PD psychosis often
leads to loss of independence, increase in caregiver burden, and nursing home placement.
Parkinson Path JULY 2016