May 2025

Certain medications block dopamine activity in the brain. If you don’t have Parkinson’s, they may cause Medication Induced Parkinsonism (also called “drug-induced parkinsonism”). If you have Parkinson’s disease, they can worsen your symptoms. In this condition, Levodopa is not very useful. This is because the sites where levodopa normally attaches are blocked by these nefarious drugs. Therefore, in this condition, both Anticholinergic medications and Amantadine are more effective than levodopa. Let us learn more. Dopamine Blockers First, here are the medications that can block Dopamine activity in the brain. “Joint position” signals going from the ankle joints to the brain are very important for balance. DOPAMINE BLOCKERS: Medications which can produce symptoms like Parkinson’s disease Many medications used for psychiatric problems such as schizophrenia (these are also called “Neuroleptics”) Haloperidol, Risperidal, Olanzapine, Aripiprzole, Trifluoperazine and many more. Clozapine and Quetiapine usually do not cause problems. Some medications for mood and depression Fluphenazine, Tranycypormine, Lithium Some anti-nausea medications Metoclopramide, Levosulpuride, High doses of domperidone about 30-40 mg/day, Flunarazine, rarely cinnarazine Some heart and blood pressure medications Amiodarone, methly-dopa Overall, Neuroleptics (psychiatric) medications are probably the most common cause of Medication Induced Parkinsonism. What is Parkinsonism? Parkinsonism literally means “like Parkinson’s disease”. Certain symptoms usually are seen in Parkinson’s disease. If a person has these symptoms, he is said to have Parkinsonism. Parkinson’s disease is the most common cause of Parkinsonism. The second most common cause in many countries is Medication Induced Parkinsonism. What is Dopamine Blockade? Dopamine is a chemical in our brains. It helps us to move. Medication Induced Parkinsonism is caused by medications which block the action of dopamine. These nefarious medications do this by blocking the microscopic sites in the brain where dopamine usually attaches itself. There is no death of cells. Dopamine-blocking medications block the sites in Brain cells where Dopamine normally attaches. Now, dopamine cannot attach itself anywhere! It stops having any effect! The cells do not die. On the other hand, in typical Parkinson’s disease, there is the actual death of cells in the Substantia Nigra (Click Here). Therefore, these processes are very different from one another. In addition, the symptoms produced by “Medication Induced Parkinsonism” are also somewhat distinct. There is usually no tremor and both sides are equally affected. Medication Induced Parkinsonism can progress very rapidly, whereas Parkinson’s disease usually progresses very slowly. Why is levodopa not useful in Medication-Induced Parkinsonism? Levodopa gets converted into dopamine in the brain. But then it has nowhere to attach! Once it enters the brain, Levdoopa is converted into Dopamine. Therefore, levodopa is not very useful in medication-induced Parkinsonism. Anti-cholinergic medications Dopamine has an enemy in the brain, called Acetylcholine. Acetylcholine actually is a good chemical with a lot of beneficial effects, but one of the things it does is to reverse some of the actions of Dopamine. Trihexyphenidyl (Pacitane) and Benztropine are the most commonly used Anticholinergic Medications. By decreasing the effect of acetylcholine (dopamine’s enemy), these medications give Dopamine a free hand in the brain. Anti-cholinergic medications: Side effects I (and many other doctors) believe that Trihexyphenidyl (Pacitane) and related medications should not be used in the elderly, at least not routinely. Acetylcholine is a very important chemical in the body, and blocking it can produce many unwanted side-effects. Therefore the most common, and frequently serious side-effects with the use of these medications are: Confusion – The patient may lose track of day and night. He/She gets confused easily, has trouble paying attention or remembering anything. In very severe cases, the patient can have visual hallucinations and become physically violent! Anticholinergics can cause confusion. Acute urinary retention – This happens more frequently in males. The urinary bladder fills up with urine, but because of the anticholinergics, the path for urine to get out is closed! The patient starts becoming very, very uncomfortable because of the ever-increasing size of the bladder, which causes severe abdominal pain. This sometimes requires the urgent insertion of a catheter. Glaucoma – Similar to what happens with urine, these medications can cause shut off the flow of fluid away from the eye. They make the pupil very large, blocking all the drainage pipes in the periphery of the eye. As a result, fluid keeps accumulating within the eye, and it starts becoming larger. The eye is not a very flexible, and therefore the pressure inside it increases rapidly, and this can cause severe eye pain and blindness. Immediate medical treatment is needed! Sometimes, anticholinergics can cause “Glaucoma” – which is an uncontrolled increase in pressure inside the eye. Amantadine Is Amantadine a better treatment for medication-induced Parkinsonism? Yes, I think so. I think so because it is equally effective and the side-effects of amantadine are relatively modest. In patients without kidney disease, Amantadine usually does not have any side-effects other than some minor leg swelling and redness. Amantadine was originally made to treat viral colds. Incidentally, doctors found it to be a stellar medication for Parkinson’s disease, including medication-induced Parkinsonism. One has to be careful while using it in patients with renal failure. Amantadine is excreted by the kidneys and therefore it accumulates in the body if you have renal failure. If it accumulates up to a toxic level, you may become confused and have jerking of the body (myoclonus). Future Does the development of “Medication Induced Parkinsonism” predict the development of “Parkinson’s disease” later in life? No, not in the majority of cases. However, some patients have a dopamine deficiency and are on the brink of developing symptoms due to Parkinson’s disease. If a person is on the brink of developing symptoms, dopamine-blocking medications lead to appearance/worsening of Parkinsonian symptoms. In these patients, dopaminergic blocking medications may cause sudden appearance/worsening of these symptoms. Physical therapy, especially balance training, can help to delay onset of Parkinson’s disease. So, in some (but not all) cases, the development of medication-induced parkinsonism may indicate that the patient may develop Parkinson’s disease later in life. Caution: This information is not a substitute for professional care. Do not change your medications/treatment without your doctor’s permission.

Read latest blog post on Meaning of Epilepsy and fill our contact form for appointment.

Read latest blog post on Meaning of Epilepsy and fill our contact form for appointment.

Parkinson’s and falling, unfortunately, go hand in hand. Most patients with Parkinson’s disease have some imbalance. In uncomplicated Parkinson’s disease, falls are less common. But: If you have recurrent falls or If you are falling backwards, Parkinson’s disease may not be the right diagnosis. If you do have Parkinson’s disease, adequate treatment helps you move properly. This prevents falls. In addition, a few general measures may also help to prevent falls and avoid serious injuries. Let us learn more. How do we maintain our balance? When the joints in your legs move, the nerves in your legs send signals to the spinal cord, from where they go to the Brain. If this system is working, then the Brain knows *exactly* where your legs are, even when your eyes are closed! This ability is called “Joint Position Sense”. “Joint position” signals going from the ankle joints to the brain are very important for balance. There are many nerves in the arms and legs (blue). These send joint position signals to the spinal cord (red), which in turn sends them to the brain (pink). A problem anywhere in this pathway can cause problems in maintaining balance. A second device is important as well: Our inner ears contain tiny circular canals filled with fluid. When your head moves, the liquid inside these canals moves, and the ears immediately send signals to the brain, informing it of this movement. The internal ear has delicate canals filled with fluid which detect head movement. Finally, your eyes. This one is obvious. When you tend to fall, you can see that you are falling. The eyes almost instantaneously send this information to the Brain, so that corrective action can be taken. Our eyes send signals to our brain almost instantaneously. The Brain is supposed to act immediately when it gets signals from any of these organs (joints/ears/eyes) that you are going to fall down. These reflex movements are called “Postural reflexes”. With this understanding, let us see now why we fall. Why do patients with Parkinson’s disease fall? In simple terms, patients with Parkinson’s disease fall down because of 3 reasons: Poor input, Poor postural reflexes, Freezing. 1. Poor input: This problem is often overlooked. When thinking about Parkinson’s and falling, we need to remember that Parkinson’s patients can also have other diseases. Let us say you have a problem with your eyes. Everything is blurred. Now, you start to walk. But…. your brain is not getting any input. It does not know where your limbs are! So, you become unsteady! Proper eyeglasses enable you to see clearly and reduce falls. So: Problems in your joints, muscles or leg nerves – e.g. Diabetes, Vitamin D deficiency Problems in your spinal cord – e.g. compression, vitamin B12 deficiency Problems in your ears – e.g. infections Problems in your eyes – e.g. improper glasses, cataracts Increase the risk of falling tremendously. This is true even if you do not have Parkinson’s disease! But let us look at 2 reasons specific to Parkinson’s disease: 2. Poor postural reflexes:1. Poor input: Let us say your brain is getting all the inputs it needs. It now knows where your limbs are. But in Parkinson’s disease, the brain becomes slow. For unclear reasons, it does not respond to these inputs immediately. This problem is called “Poor Postural Reflexes”. Poor postural reflexes: The brain is slow in processing inputs and outputs needed for balancing. Let’s imagine you catch your foot in the carpet. When you start to fall, your brain is too slow to take corrective measures. It does nothing. So you fall. This is one of the reasons for Parkinson’s and falling. 3. Freezing: When walking, you may sometimes feel like you are stuck to the ground. This is called “Freezing”. If this happens suddenly, your upper body may continue moving and you may fall forwards. If your movement problems are incompletely treated, you can “Freeze” suddenly while walking and fall forwards. Is freezing really the reason for falling? Some people believe that “freezing” while walking can lead to falls. In contrast, other people believe that the freezing before falling is an erroneous reflex by the Brain, which is just trying to prevent a process of falling which has already started happening. Regardless of what comes first, it is clear that making movements more rapid with proper treatment helps to prevent falls. So, how can you prevent falls? The first step is to identify why you are falling. The relative contribution of these factors to falling is different in different patients. Thoughtful collaboration with your neurologist should help to identify your most critical problems. We will look at each of these things in detail, one by one. If you have Parkinson’s and falling backwards, a very important possibility arises. Your doctor should carefully examine you for signs of PSP. PSP is described in another article [Click here]. Careful examination & collaboration usually identifies 1-3 critical problems causing falls. Prevent a drop in Blood Pressure on standing When you get up suddenly from a chair or bed, your blood rushes into your legs. This causes blood pressure to drop. You may become light-headed & fall. This is called Orthostatic Hypotension. It is very common in Parkinson’s disease. You can read more in another article, but here is a quick summary: Prevent Orthostatic Hypotension 1. Avoid medications that may worsen this problem. 2. Drink enough water. 3. If your doctor agrees, slightly increase salt in your diet. 4. Stand up gradually. 5. Exercise & develop better muscle tone. 6. Ask your doctor for medications. Adequate sensory input A neurological examination can test the input organs (nerves, spinal cord, ear, eyes). For example, your may ask you to close your eyes and move your big toe up and down. If you are unable to tell whether it is up or down, it indicates there is something wrong with your “joint position sense”. Your neurologist may ask you do some tests: Tests to check sensory organs (input) 1. Nerve conduction studies 2. MRI of the spine 3. Blood tests – Vitamin B12, Folic acid, E & Copper, Syphilis &

Read latest blog post on Meaning of Epilepsy and fill our contact form for appointment.

(Brand names in India: Amantrel, Parkitidin) How does Amantadine act? Amantadine is a another friend of levodopa (remember: its other friend is entacapone). While it can decrease the symptoms of Parkinson’s disease, it works best when it is given to support the action of levodopa. While Entacapone can sometimes increase the side-effects of levodopa, Amantadine is the friend who smoothens out your rough edges, makes you a better person. Amantadine decreases some side-effects of levodopa and makes it more wonderful. Levodopa’s two friends: Entacapone & Amantadine. No one quite understands how Amantadine works for Parkinson’s disease. It was originally designed to kill the influenza virus. However, doctors accidentally discovered that it makes Parkinson’s disease better as well. It has one, fantastic and unique effect in Parkinson’s disease that is described below. No one quite understands how Amantadine works for Parkinson’s disease. It was originally designed to kill the influenza virus. However, doctors accidentally discovered that it makes Parkinson’s disease better as well. It has one, fantastic and unique effect in Parkinson’s disease that is described below. Use/Advantages: Treatment of “Dyskinesias”: Some patients with Parkinson’s disease start getting bothersome movements of the hands, legs and neck after a few years of treatment. I want you to understand these movements. So with all respect: please allow me to describe these movements in the simplest way possible. These movements are dance-like movements, somewhat similar to the way Michael Jackson dances on stage. The Latin word for dance is chorea, and therefore these movements are called chorei-form (dance-like) movements. Since that word is very complicated, they are also called “Dyskinesias”. These movements are often time-linked to levodopa. They are maximum in intensity 30 min – 1 hour after taking levodopa. Dyskinesias are dance-like movements. Amantadine has one fantastic effect – it decreases these movements tremendously. For patients who have not been able to take enough levodopa because of these movements, it enables intake of an adequate quantity of levodopa, so that they can have a much better quality of life. It may smoothen-out the effect of levodopa, and can help in relieving “Predictable wearing OFF” to some degree. But, other stratergies such as entacapone, long-acting medications etc are much more useful for this purpose. Rarely, it can be given as the only medication for Parkinson’s disease. But when used by itself, its effectiveness is limited. Disadvantages: Most people don’t have any side-effects from Amantadine. Some people can have mild swelling or slight purplish discolouration of the feet. Since it is an anti-viral, it can decrease the effectiveness of some viral vaccines. If a live viral vaccine (e.g. Hepatitis B vaccine) needs to be given, Amantaide should be stopped 2 weeks prior and 2 days after the vaccine is administered. Amantadine can decrease the effectiveness of some vaccines. Bottom-line: It is used to control troublesome dance-like movements caused by high doses of levodopa. Although it is only modestly effective by itself, it is extremely good at smoothing out the rough edges of our superstar (levodopa), hence the sorbiquet – The lawyer of levodopa. Caution: This information is not a substitute for professional care. Do not change your medications/treatment without your doctor’s permission.

Read latest blog post on Meaning of Epilepsy and fill our contact form for appointment.

After reading what your doctor wrote, you may have wondered: What is PSP? PSP means “Progressive Supranuclear Palsy”. It is a Parkinson’s Plus Syndrome. Some diseases are like Parkinson’s disease. But they also have extra symptoms. So, they are called “Parkinson’s Plus Syndromes”. PSP is the most common Parkinson’s Plus Syndrome. If you have PSP, the extra symptoms will be: (1) Falling (2) Trouble moving eyes. In the early stages, PSP may be misdiagnosed to be Parkinson’s disease. An MRI may help in the accurate diagnosis of PSP. Parkinson’s Plus Syndromes You can read more about Parkinson’s plus syndromes here. Do read about misdiagnosis here. It will help you understand this article. Symptoms of PSP Progressive Supranuclear Palsy (PSP) has the 4 cardinal symptoms of Parkinsonism. 4 movement problems = “Parkinson-ism” 1. Slowness (Bradykinesia, Hypokinesia or Akinesia) 2. Uncontrolled shaking (tremor) 3. Stiffness (rigidity) 4. Unsteadiness & shuffling gait. All features are not always present. In particular, PSP patients often do not have a tremor. Parkinson’s Plus syndromes have extra symptoms. So, let us look at the “Plus” symptoms of PSP PLUS symptoms seen in PSP (Extra) 1) Falling: Falling can happen both in Parkinson’s disease and PSP. But, patients with PSP start falling early. Usually, PSP patients will fall within one year. Also, patients with PSP will fall backwards. Falling, mostly backwards, is seen in PSP. If you have PSP, you may walk with your feet wide apart to prevent falls. Falls are a big problem. They can cause injury. So, it would help if you took all measures to prevent them. Click here to learn how. 2) Trouble moving eyes: Usually, the doctor notices this problem. If you have Progressive Supranuclear Palsy (PSP), you will have difficulty moving your eyes. It becomes difficult to look up and look down. Partly because of this problem, you may sit with their head pushed backwards. (hyperextension of the neck). Look at the video below, posted by Dr. Dusan Pavlovic on youtube. This patient has trouble looking upwards. He also has some difficulty looking down. When present, difficulty looking downwards is very suggestive of PSP. https://www.youtube.com/watch?v=LU7TC0wufhg Here is another video, by Dr. Kathleen Digre at the University of Utah. It is good to know what doctors look for. But, this video is very technical. It’s okay if you do not understand it completely. https://www.youtube.com/watch?v=JlIWSilgPvc Other Plus symptoms of PSP Falling & trouble moving eyes are the main plus signs. But patients with PSP also have the other additional problems: Usually, PSP patients will fall within one year. Also, patients with PSP will fall backwards. 1. Speech: They may need to strain to talk. It may seem like they have a strangled voice. They may stutter or repeat words. 2. Swallowing: It may be difficult to push food into the stomach. Food may go into the lungs instead (aspiration). This may cause explosive coughing. If food goes into the lungs, it causes a nasty pneumonia. This is called “Aspiration”. Aspiration is a serious issue. It needs urgent attention. Read more about prevention of aspiration here. 3. Thinking: PSP patients have difficulty controlling their emotions. They may laugh or cry very easily (pseudo-bulbar affect). PSP patients may become impulsive. They may get up quickly, even though this makes them fall. Doctors call this the “rocket sign.” What causes Progressive Supranuclear Palsy (PSP)? Progressive Supranuclear Palsy (PSP) is caused by an accumulation of a waste product called “Tau” in the brain. Remember: Parkinson’s disease is caused by the collection of waste produced called “synuclein.” Accumulation of a waste product called “tau” in the brain may cause PSP. Accumulation of tau causes a decrease in dopamine activity in the brain. The exact reason why “Tau” accumulates in the brain is not known. How is PSP diagnosed? PSP is diagnosed clinically. It is diagnosed by the doctor talking to you and examining you. The most important things are: – History of frequently falling backwards, especially in the first year. – Difficulty looking downwards when the doctor examines you. A detailed conversation with and examination by your doctor is needed to diagnose PSP. Accumulation of tau causes a decrease in dopamine activity in the brain. The exact reason why “Tau” accumulates in the brain is not known. What are the MRI findings of PSP? These findings are not seen in all patients. In particular, they may not be seen in the early stages of Progressive Supranuclear Palsy (PSP). In PSP, a particular part of the brain called the”Midbrain” shrinks in size. When this happens, the following two signs may be seen on the MRI: Mickey-Mouse sign: When seen from the top, the midbrain may appear like Mickey-Mouse. Humming-bird sign: When seen from the side, the midbrain may appear like a hummingbird. Click here to see images: [Menoufia University Journal Article] Sometimes, these findings are not seen on the first MRI. In those cases, a repeat MRI after 1-2 years may show these changes. Can an F-DOPA scan or Trodat Scan diagnose PSP? Yes. F-DOPA or Trodat scans detect a decrease in dopamine activity in the brain. You can read more about them here. This is a DAT scan. The scan on the right shows decreased dopamine activity. Dopamine activity is reduced in Progressive Supranuclear Palsy (PSP), like in Parkinson’s disease. So, these scans are abnormal. The scan findings in PSP are slightly different than Parkinson’s disease. But these differences are slight. So, it isn’t easy to distinguish PSP from regular Parkinson’s disease based only on DAT / FDOPA studies. What is the treatment of PSP? You can read more about the treatment of PSP in another article. [Click here] PSP patient guide 1. What are the Parkinson’s Plus syndromes?2. What is PSP?3. 30+ Mimics of Parkinson’s & PSP 4. PSP treatment & new research:   (a) Do we have a miracle cure for PSP?   (b) Levodopa – actions & side-effects   (c) Amantadine – actions & side-effects 5. How to avoid aspiration6. How to avoid falling7. Avoid these medications!8. Get updates by email Caution: This information is not a substitute for professional care. Do not