Parkinson’s is a progressive neurological disease. People with Parkinson’s experience various physical, cognitive, and psychological symptoms.

Often, the early symptoms of Parkinson’s are so subtle that the disease goes unnoticed for years. As the disease progresses, a lack of motor skills becomes more apparent. This is followed by cognitive impairments, including trouble following directions and loss of thought.

Understanding the symptoms of Parkinson’s is key to getting the right treatment. In this article, we’ll talk about what the different stages of Parkinson’s can look like and go over the symptoms in-depth.

Parkinson’s symptoms can be divided into three categories or phases: pre-motor, motor, and cognitive. These phases don’t necessarily happen in chronological order, and not all Parkinson’s patients will experience all symptoms.

The premotor phase is the phase of Parkinson’s in which non-motor symptoms are present. These symptoms include:

Motor symptoms generally involve movement and include:

Approximately 50 percent of people with Parkinson’s will experience some form of cognitive impairment, with severity varying among individuals.

Cognitive changes can include:

  • problems with attention
  • slowed mental processing
  • trouble with problem-solving or executive functioning
  • memory deficits
  • language abnormalities
  • visuospatial difficulties

Parkinson’s is a chronic and progressive disorder, meaning that symptoms grow worse over time. There’s a wide range of symptoms and symptom severity: while some people become severely disabled, others have only minor motor problems.

Tremors

A tremor is an unintentional, rhythmic muscle movement involving one or more parts of the body. Tremors primarily occur in the hands but can also affect:

  • arms
  • head
  • face
  • voice
  • torso
  • legs

There are two main categories of tremor: resting tremor, and action tremor. Resting tremor occurs when muscles are relaxed, like when your hands are sitting in your lap, and lessen during sleep or when the body part is in use. Action tremors occur with the voluntary movements of a muscle.

Tremors typically affect only one side of the body but may affect both sides as the disease progresses. Fatigue, stress, and intense emotion may worsen tremors.

Slowed movement (bradykinesia)

Bradykinesia means slowness of movement and is a hallmark symptom of Parkinson’s. It can manifest in various ways, including:

  • difficulty initiating movements like standing up
  • slowed automatic movements like blinking
  • general slowness in physical actions like walking
  • the appearance of “abnormal stillness” in facial expressions

Speech changes

Among people with Parkinson’s, 89 percent experience speech and voice disorders. These disorders include changes to the voice that might make it sound soft, monotone, or hoarse.

People with Parkinson’s may not be aware that their speech is soft and difficult to understand, and may feel as though they are shouting when they are actually speaking normally.

Impaired posture and balance

Postural instability is the most difficult Parkinson’s symptom to treat, and one of the most important criteria for diagnosing Parkinson’s.

Postural instability is the inability to balance due to loss of postural reflexes and often leads to falls. Patients with impaired posture and balance might revert to a stooped posture and have a shuffling gait.

Muscle rigidity

Muscle rigidity refers to stiffness in the arms or legs. Rigidity may occur on one or both sides of the body and can lead to a decreased range of motion, causing achiness or pain in affected muscles or joints

Loss of automatic movements

People with Parkinson’s commonly experience a gradual loss of automatic movements, which can lead to a decreased frequency of blinking, swallowing, and drooling.

Writing changes

Small, cramped handwriting called micrographia is a common early symptom of Parkinson’s. Handwriting size may get smaller as you continue to write, and your signature may change over time.

Constipation

Constipation is defined as having fewer than three bowel movements per week. In people with Parkinson’s, constipation often begins before motor symptoms.

It’s believed that constipation in some people with Parkinson’s may be due to improper functioning of the autonomic nervous system, which controls the muscle activity of the gut and enables bowel movements.

Diminished sense of smell

Hyposmia, or reduced sense of smell, is often an early sign of Parkinson’s, predating motor symptoms by several years. It occurs in about 90 percent of early-stage Parkinson’s cases.

REM-sleep behavior disorder

REM-sleep behavior disorder (RBD) is a sleep disorder where a person physically acts out vivid dreams with sounds or sudden arm and leg movements during REM sleep. Symptoms include:

  • kicking, punching, or flailing during sleep
  • making noises like yelling, talking, or laughing
  • being able to vividly recall dreams

RBD often precedes or follows the onset of Parkinson’s and may be associated with the development of hallucinations and dementia.

One study found that 66 percent of people with RBD developed a neurodegenerative disease within 7.5 years, suggesting a strong connection between RBD and the risk of neurodegenerative diseases like Parkinson’s.

Anxiety and depression

Some people diagnosed with Parkinson’s may experience some form of depression or an anxiety disorder.

Some symptoms of depression — like sleep issues, low energy, and slowed thinking — overlap with symptoms of Parkinson’s, making it difficult to diagnose.

Depression and anxiety may also pre-date other symptoms of Parkinson’s.

Low blood pressure when standing

Orthostatic hypotension (OH) refers to a persistent drop in blood pressure that occurs when you move from sitting to standing, or from lying down to sitting up or standing. It can cause:

  • dizziness
  • lightheadedness
  • weakness
  • difficulty thinking
  • headache
  • feeling faint

OH is defined as a blood pressure drop of 20 millimeters of mercury in systolic blood pressure, or a drop of 10 millimeters in diastolic blood pressure.

Drooling

Sialorrhea, or excessive drooling, is a common symptom of Parkinson’s. People with Parkinson’s often have trouble with automatic actions, like swallowing, which can result in saliva pooling in the mouth.

This can happen when the head is down, when the mouth is held open involuntarily or when a person is distracted and doesn’t swallow automatically.

Increased urination urgency and frequency

Bladder problems are a common occurrence in people with Parkinson’s, occurring in 30-40 percent of people with the disease. The most common urinary symptom is a frequent and urgent need to urinate even when the bladder is empty, as well as trouble delaying urination.

Trouble emptying the bladder is a less common feature of Parkinson’s urinary dysfunction. It may be caused by difficulty in relaxing the urethral sphincter muscles that allow the bladder to empty.

Difficulty swallowing or eating

Parkinson’s affects the muscles in the face, mouth, and throat that control speaking and swallowing. Dysphagia, or difficulty swallowing, is a symptom of Parkinson’s that can lead to trouble eating.

It can lead to malnutrition, dehydration, or aspiration — which happens when food or saliva “goes down the wrong pipe” and is inhaled into the lungs. Aspiration can lead to aspiration pneumonia, the leading cause of death in Parkinson’s.

Erectile dysfunction

Sexual dysfunction is common in people with Parkinson’s disease, with 54-79 percent of men reporting erectile dysfunction. Erectile dysfunction in people with Parkinson’s is believed to be linked to the disease’s effects on the central nervous system, as well as issues with blood circulation and control of pelvic muscles.

Eye problems

Vision changes are common as people grow older, but some vision changes may be specifically linked to Parkinson’s. Parkinson’s can cause the following:

  • dry eyes as a result of decreased blinking
  • double vision due to the eye’s inability to work together
  • trouble reading
  • involuntary closure of the eyes
  • trouble voluntarily opening the eyes

Some Parkinson’s medications, particularly anticholinergics, can cause blurry or double vision.

Slowed thinking

Cognitive impairment in people with Parkinson’s can range from feelings of distraction and trouble planning tasks to more severe cognitive impairment that interrupts everyday life.

Cognitive changes in people with Parkinson’s are believed to be linked to drops in dopamine as well as changes in the brain levels of acetylcholine and norepinephrine.

Signs of slowed thinking include:

  • taking longer to complete tasks
  • difficulty retrieving information from memory
  • delays in responding to stimuli

Impaired memory

The basal ganglia and frontal lobes of the brain, two areas that help with information recall, may be damaged in people with Parkinson’s. This can result in trouble with normal tasks like using a phone or making a meal.

People with Parkinson’s may also have trouble remembering words, known as the “tip of the tongue” phenomenon.

Difficulty paying attention

People with Parkinson’s often report difficulty with completing tasks that require them to concentrate and maintain their attention. This can make it hard to focus on situations that require divided attention, like group conversations.

Dementia

Some people with Parkinson’s will eventually develop Parkinson’s disease dementia. People with dementia have permanent cognitive and motor impairments that significantly impact their daily life.

Mental impairment must affect at least two brain functions to be considered dementia. Mental impairment can range from mild to severe and could cause personality changes.

If you’re experiencing early non-motor symptoms of Parkinson’s — like depression, constipation, or loss of smell — you may be concerned about Parkinson’s risk. In this case, you should schedule an appointment with a neurologist who can conduct a neurological exam.

If you have motor symptoms of Parkinson’s — like tremors, rigidity, or postural instability — your doctor will likely conduct a dopamine transporter imaging test, known as a DaTscan, which can determine if you have a dopamine deficiency.

Remember: Non-motor symptoms like depression and constipation are common in the general population. So, just because you have them doesn’t mean you have or will develop Parkinson’s. If you’re concerned about symptoms, keep track of how often they affect you so you can give as much information as possible to your doctor.