Motor Symptoms of Parkinson's
Reviewed by: HU Medical Review Board | Last updated: June 2022
Parkinson’s disease (PD) is a movement disorder that gets worse over time. PD progresses differently for everyone. You may experience different symptoms at different times than someone else living with PD.1
Symptoms of PD are generally mild at the beginning. The most common early symptoms include:1,2
- Trouble standing after sitting
- Stiffness in the limbs
- Moving more slowly
What are the most common symptoms?
There are 4 main motor symptoms of PD:1
- Tremor at rest, such as a slight tremor in the hands or feet
- Rigidity (stiffness) of limbs, neck, or shoulders
- Difficulty balancing (postural instability)
- Slowness of movement or gradual loss of spontaneous movement (bradykinesia)
Parkinson’s can sometimes be confused with other movement disorders. Doctors begin to think about PD when they see bradykinesia with either tremor or rigidity. These symptoms are seen from the start of the disease.1
What are other motor symptoms
- Masked facial expressions (hypomimia)
- Decreased blinking
- Speech issues, such as a monotone voice or soft speech
- Problems swallowing (dysphagia)
- Eye problems, such as blurred vision, abnormal eye movements, and inability to open the eyes at will
- Small, cramped handwriting (micrographia)
- Involuntary muscle contraction that cause repetitive or twisting movement (dystonia)
- Stooped posture
- Walking issues, such as shuffling, freezing, and short, quick steps and a hunched posture
There are other symptoms of PD that are not directly related to movement dysfunction. These non-motor symptoms include depression, memory loss, difficulty sleeping, and hallucinations. You may experience many of these symptoms or only a few.1
What causes them?
Though PD can affect the whole body, it starts in the brain. It begins when neurons in an area of the brain called the substantia nigra are damaged or die. The brain cells in this area create dopamine. Dopamine is a chemical that sends messages between neurons. It is used to send messages to another area, called the basal ganglia.1
When neurons in the substantia nigra die, there is not enough dopamine made to properly "talk" to the basal ganglia. The basal ganglia helps coordinate muscle movements.1
Without dopamine, the basal ganglia’s communication to areas of the brain that control muscle movement is disrupted. Without proper basal ganglia input to help coordinate movements, it is hard to make quick or smooth movements.1
How are they treated?
There is currently no known cure for PD. However, there are treatments that can help manage symptoms of the disease.
Because PD symptoms are caused by low dopamine in the brain, many treatments focus on increasing dopamine. There are a wide variety of drugs to treat motor symptoms. They can be combined in many ways to best treat different symptoms.
The drugs are divided into different categories:4
- Levodopa/carbidopa – Levodopa is a chemical that the brain can directly turn into dopamine. Carbidopa is often added. It makes sure that levodopa does not turn into dopamine until it reaches the brain.
- Dopamine agonists – These drugs are not turned into dopamine but can act like dopamine in the brain.
- Anticholinergics – Acetylcholine is another messenger chemical in the brain. It also works on muscles. These drugs block acetylcholine, creating a better balance between dopamine and acetylcholine.
- MAO-B inhibitors – MAO B is an enzyme in the brain that breaks down dopamine. These drugs prevent that breakdown so dopamine lasts longer.
- COMT inhibitors – COMT is an enzyme that breaks down levodopa. These drugs prevent that breakdown. This allows more levodopa to reach the brain so it can be changed into dopamine.
- Amantadine – This drug increases how much dopamine is released by neurons.
It may take a few tries to find the right combination of drugs and doses for you. You also may need to add drugs, stop taking drugs, or change doses as your Parkinson’s progresses.3