Planning for the What-Ifs — Mental health concerns in advanced PD – psychosis and behavioral problems

Planning for the What Ifs

Mental Health Concerns in Advanced Parkinson’s Disease

Today we continue Parkinson’s Disease: Planning for the What Ifs, a special series of posts to address both motor and non-motor issues of people with advanced Parkinson’s disease (PD). We are defining advanced PD as those who are no longer independent of their activities of daily living, and require help for their self-care such as eating, bathing, dressing and toileting. Additional background and the full introduction to the series is still available if you missed it.

I receive a lot of questions through our Ask a Doctor feature on our website concerning advanced PD, specifically around mental health issues.

Read Messages from Our Community Related to Mental Health in Advanced PD:

“My Dad fights aggressively when his aides try to get him to do something he doesn’t want to. He gets so angry and is so strong it can take many people to restrain him.”

My Mom lives at home, but constantly thinks that she is somewhere else and wants to go home. She becomes irritated and angry with the family because she says that we are holding her hostage.”

“My husband is verbally abusive towards me. This is an entirely new aspect to his personality. He was always very loving. Now he is aggressive.”

“My wife is severely depressed. Although she can get out of bed with help, she would rather stay in bed and do nothing. She also doesn’t seem to mind that she is doing nothing all day.”

“Often, my brother doesn’t recognize me when I visit. Last week, I saw my brother in the morning, but when I spoke with him on the phone later on in the evening, he mentioned that he had not seen me in a long while.”

These quotes highlight a set of very problematic issues in advanced PD which include cognitive decline/dementia, depression, apathy, anxiety, psychosis (which encompasses hallucinations, delusions, paranoia), and behavior problems (which encompasses anger, aggression, agitation, irritability, personality changes, mania, impulse-control disorders). One person often has a mixture of these symptoms and the symptoms can be inter-related.

General principles when facing mental health issues in PD

  • Consider other illnesses or conditions – The first thing to remember when dealing with these mental health issues, especially if they seem to arise suddenly, is that many can be triggered or exacerbated by the presence of another illness or condition. A very common scenario is that cognition seems to worsen suddenly or hallucinations start or worsen suddenly, and this is the presenting sign of a urinary tract infection. Learn about other modifiable contributors to cognitive decline in PD, along with other mental health concerns as well. Besides inter-current infection, these conditions include abnormal thyroid function and head trauma.
  • Review medications with the doctor – Certain medications given for urinary frequency, migraine, seizures, anxiety, and other conditions, can interfere with cognitive function or cause hallucinations. Be sure to review all medications frequently with the neurologist.
  • Consider lowering PD meds – Medications given for the motor symptoms of PD can cause psychosis, mania and impulse-control disorders and can also contribute to some of the other mental health concerns. The doctor may therefore consider lowering medications for the motor symptoms, which may mean that the person with PD has worsened motor function, in order to get the mental health issues under better control.
  • Remember this is part of the disease – If no additional condition or medication is identified that is contributing to the mental health problems, and medications for PD can’t be lowered any further, remember that the issue that you are witnessing is part of the Parkinson’s disease process and not anyone’s fault.
  • Ensure the safety of the person, and everyone around him/her – This may mean calling for help, possibly even 911.
  • Non-drug approaches to managing mental health issues in people with advanced PD should be tried first, tailored to the particular mental health issue that is problematic. This will be discussed below.
  • Treat what can be treated – Consider medications to treat the symptoms that can be treated. For some of these mental health problems, there are medications that can be prescribed to help. For others, there are no easy answers. Typically, discussions of mental health issues in advanced PD tend to mention only those issues for which there are medications available for treatment such as cognitive decline, depression, anxiety, and psychosis. (We will talk about these treatments later). Other very problematic issues do not have approved medications to help, including behavior problems (anger, aggression, agitation, irritability, personality changes) and apathy. (Doctors may try medications that are approved for other conditions to try to help these symptoms – more on this later.)It is important to note that underlying the anger, aggression, agitation, irritability, personality changes or apathy, may be cognitive decline, depression, anxiety or psychosis. For example, in the first case above, the person with Parkinson’s is outwardly angry and aggressive. But is it possible that he is perceiving the aides as trying to hurt him and that delusional thinking is causing the aggression? If this is the case, then treating the delusional thinking may be helpful.


We will examine each of the mental health symptoms that can affect those with advanced PD and discuss non-medication as well as medication management approaches. The rest of this blog will be dedicated to psychosis and behavior problems.  We will address the other mental health issues and symptoms in future blogs in this series.


This set of symptoms encompasses hallucinations, delusions and paranoia. Symptoms of psychosis can be very variable in their manifestation and severity. In addition, the degree of insight into the psychotic thought or vision can be variable as well. As mentioned above, psychosis can lead to behavioral symptoms and needs to be explored as a possibility when behavioral symptoms arise. They can also exist independently of any behavioral symptoms. People with PD are often very reluctant to report these symptoms, for fear that they will be perceived as “crazy”.

Of note, hallucinations are a risk factor for dementia and dementia is a risk factor for hallucinations.


Hallucinations are false perceptions. In PD psychosis, hallucinations are usually visual, but they can involve the other senses such as auditory or tactile hallucinations. A person may experience presence hallucinations, during which he or she feels that someone or something is next to them, but when he or she turns to look, nothing is there. In addition, a hallucination may be a fleeting image, perceived out of the corner of a person’s eye, which dissolves when the person turns his/her attention to it.

People with PD often have hallucinations of small, furry animals. The hallucination can also be of people, sometimes relatives who have passed on. The people in the hallucination tend to be silent, and do not interact with or even look at the person having the hallucination.

Delusions are fixed beliefs that contradict reality or rational argument. In PD psychosis, delusions can be of a paranoid nature, including the belief that someone is stealing or that a spouse is having an affair.

Severity of hallucinations

The severity of hallucinations varies greatly from person to person. Some hallucinations can be mild, and not bothersome. Sometimes, they can even be pleasant. They can be intermittent and infrequent. However, on the other end of the spectrum, hallucinations sometimes can be very disturbing or even gruesome, and can be persistent.


Some people are aware they are experiencing hallucinations, others are not. A person may misinterpret his/her surroundings and for example, see a pillow as a dog, a vision which dissipates as the person gets closer to the object. A person may also see an image which he/she is able to recognize as a hallucination. On the other hand, a person may see an image that he/she is not able to distinguish from reality. Sometimes a care partner can explain that the image is a hallucination, and this brings insight. Sometimes, no amount of explanation can bring insight and the person with PD is convinced that the hallucination is a part of reality.

Sometimes insight into the hallucination is reassuring. Sometimes however, knowing that the vision is not a part of reality is upsetting in its own right.

Non-drug approaches

As mentioned above, inter-current illness can trigger psychosis and must be investigated. Medication lists must be reviewed for those that may contribute to psychosis. PD meds may need to be lowered in order to address psychosis. If none of these methods lead to a resolution of hallucinations, consider these approaches.

  • If the hallucination is not bothersome, no action may need to be taken.
  • If the person with PD asks if you see the hallucination, respond honestly that you do not see the hallucination, but validate that you understand that he/she does see something that appears very real to him/her and can be very scary.
  • Offer reassurance that the person is safe and that the hallucination is not harmful.
  • Try distracting the person from what appears to be bothering him/her.
  • Identify any sounds or shadows/lighting around the person’s environment that could be misinterpreted and try to modify these potential triggers of hallucinations.

Use of anti-psychotic medications

If hallucinations are bothersome enough to interfere with quality of life and none of the non-pharmacologic methods improve the situation, an anti-psychotic medication may be necessary.

However, it must be noted that all anti-psychotic medications carry an FDA-required black box warning which states that patients with dementia taking anti-psychotics have a higher death rate than those who do not, mostly from cardiovascular disease and pneumonia. Because of this, anti-psychotics in this population should never be used as a method of sedation and should only be used if symptoms are causing significant distress or are an obstacle to providing basic hygiene or medical care.

In addition, most anti-psychotic drugs block the dopamine system and can cause symptoms that are similar to the motor symptoms of PD. Most of these medications can therefore significantly exacerbate the motor symptoms of PD and cannot be used in PD. One medication, pimavanserin, modifies the serotonin system (not the dopamine system) and is approved for use in PD psychosis. Two other anti-psychotics, quetiapine and clozapine, are safe to use in PD even though they do modify the dopamine system and are used off-label (which means that a drug approved for one purpose, is used to treat a different condition) for treatment of psychosis. Clozapine carries a known risk of decreased white blood cell count and requires weekly, and then monthly, blood tests to monitor for this side effect.


Anger, aggression, agitation, irritability and personality change can be a very difficult set of symptoms for loved ones to deal with, especially since they can occur in those who previously had very calm personalities. Outbursts can manifest verbally or physically and can occur in response to a clear stimulus or without clear cause. Those with significant behavioral problems almost always have cognitive impairment as well.

Impulse control disorders (ICD) in which a person is unable to control urges or compulsions can be a side effect of dopaminergic medications. Compulsivity can manifest in many ways, for example, as gambling, hyper-sexuality or over-shopping. Mania, an over-excited mood state characterized by symptoms such as inappropriate elation and over-activity, can also be a side effect of dopaminergic medications.

Non-drug approaches

  • Search for an underlying trigger. Besides looking for a medical illness or medication side effect that could be contributing to the behaviors, consider whether there is an underlying trigger that you can potentially fix. For example, is the person in pain or discomfort? Tired? Hungry? Thirsty? Constipated? Retaining urine? Is there too much stimulation in the environment with too much noise or people? Is the environment new, leading to confusion about where he is or who is around him? Think about what might have prompted the behavior and if there is a pattern that emerges.
  • Consider whether the behavior is a sign of an off period, when effects of PD medication are waning. If this is the case, dosages or timing of medication may be able to be adjusted.
  • Consider whether the behavior is due to the PD meds themselves – ICDs and mania for example may need to be treated by lowering PD meds. Particular PD meds may be more inclined to induce ICDs than others, so discuss this with the neurologist.
  • Respond with calm – Do not argue about the facts and do not take the behavior personally. Provide simple explanations. Be positive and reassuring. Speak slowly and in a soft tone. Play soft music.
  • Limit confusion – Try to limit the confusion in the immediate environment, by decreasing noise and clutter.
  • Redirect the person’s attention by focusing him on a different topic or task.
  • Establish a routine to minimize novelty that may trigger confusion.
  • Correct vision and hearing loss to help decrease confusion.
  • Join a care partner support group to both get and share ideas with others.


Medication approaches

Sometimes the above non-pharmacological methods are not enough to control the behavior. It is important to understand that there are no FDA approved medications to treat behavioral symptoms in the advanced PD patient. Medications are sometimes used off-label. If evidence for the use of these compounds for behavioral symptoms does exist, it is nearly always limited to their use in Alzheimer’s dementia and not advanced PD. Even though none of the medication classes listed below have robust evidence for their use, they are sometimes tried nevertheless because behavioral symptoms can be so disruptive. It must also be noted that many of these medications can cause increased falls, sedation and confusion, so the risks of using these medications must be weighed against any potential benefit.

  1. Anti-depressants – Anti-depressants may be helpful to reduce irritability. Selective serotonin reuptake inhibitors (SSRIs) are usually tried first, but there are many different types of anti-depressants that are available with different side effect profiles, and others can be tried if SSRIs are not effective. It is important to note, that these medications as a rule need to build up in the body and might not take effect for 4-6 weeks.
  2. Anti-anxiety medications – Anti-anxiety medications may help agitation. These medications work quickly, but can also lead to sedation, increased imbalance and increased confusion, so they need to be used with caution.
  3. Anti-psychotics –  Remember, most anti-psychotic medications can not be used in PD patients (see discussion in the Psychosis and Advanced PD section above), so this discussion is limited to the anti-psychotic medications that can be used in PD. Anti-psychotics may be used for anger, aggression, and severe agitation. In must be noted that sometimes these behavioral problems can be a manifestation of psychosis itself, making treatment with an anti-psychotic even more compelling. For example, someone who suspects that his aide is stealing his money or that his wife is having an affair may get very angry. Someone who sees disturbing visions in his house but is unable to verbalize what he is seeing, may appear very agitated. All other issues concerning use of anti-psychotics in this population are the same as in the above-mentioned discussion of anti-psychotic use.
  4. Cholinesterase inhibitors – These are medications approved for treatment of dementia. Some practitioners use these medications off-label for behavioral problems such as agitation.
  5. Anti-epileptic medications – These are medications approved for use in epilepsy, but are used off-label for mood stabilization. Valproic acid, carbamazepine, lamotrigine and gabapentin are sometimes tried for behavioral symptoms, but data for their use is limited and mixed.

Tips and Takeaways

  • Mental health concerns in advanced PD encompass cognitive decline/dementia, depression, apathy, anxiety, psychosis (which encompasses hallucinations, delusions, paranoia), and behavior problems (which encompasses anger, aggression, agitation, irritability, personality changes).
  • Remember that for many, PD does not reach an advanced stage where mental health issues become problematic.
  • Bring any mental health issues to the attention of the health care team right away so you can discuss ways to mitigate the issues.
  • If these problems arise, first consider whether it is being caused by a medication side effect or another medical illness.
  • If not, consider non-drug approaches first like modification of the environment and redirection of the person’s attention.
  • There are few medications that are FDA approved for these problems, but many are tried off-label if necessary. You’ll need to work closely with the health care team to evaluate which medications may/may not be worth trying.
  • Mental health issues can be very challenging and upsetting to the care partner. Consider joining a care partner support group – contact APDA (1-800-223-2732) for help in locating one near you.

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