How Is Parkinson's Disease Treated?

Parkinson’s disease (PD) is a chronic, progressive disease that affects the nerve cells in the brain and the body. It is not known exactly what causes the disease. However, scientists believe it to be a combination of genetic and external factors.

Current treatments reduce the motor symptoms of PD. However, there is no known cure for PD. There are also no treatments that can slow the progression of the disease.

Treatment for PD is focused on managing the symptoms to improve quality of life. While PD has some common features and symptoms, the disease can show up differently in different people.

Treatment is customized to meet the unique needs of each person and may include:

• Medicines
• Surgery (deep brain stimulation)
• Physical rehabilitation
• Exercise
• Complementary and alternative medicines

Treating the motor symptoms of Parkinson’s disease

Motor symptoms are those that affect a person’s ability to move. PD is characterized by 4 primary motor symptoms:^1,2

• Tremor – A shaking of the hands, arms, foot or legs, when the limb is at rest. Usually seen only on 1 side of the body.
• Rigidity – An abnormal stiffness in a limb or part of the body. May include small jerks or ratchet-like movements.
• Postural instability – Impaired balance or difficulty standing or walking.
• Bradykinesia – Gradual loss and slowing down of spontaneous movement.

Along with the primary motor symptoms, PD may cause a number of secondary motor symptoms, including:^2,3

• Freezing of gait or shuffling gait
• Micrographia (abnormally small or cramped handwriting)
• Unwanted accelerations in movement or in speech
• Speech difficulty or changes in speech
• Stooped posture
• Dystonia (prolonged muscle contractions that can cause twisting of body parts or repetitive movements)
• Impaired fine motor dexterity
• Poverty of movement
• Akathisia (restless movement)
• Difficulty swallowing
• Cramping

Initial therapy for motor symptoms of PD usually includes:⁴

• Levodopa given along with carbidopa
• Dopamine agonists
• Monoamine oxidase-B (MAO-B) inhibitors

The combination of levodopa and carbidopa is the most effective treatment available for the management of motor symptoms of PD. However, it can cause a side effect known as dyskinesia, which is abnormal involuntary movements. Plus, carbidopa-levodopa therapy can cause fluctuating symptoms of "on" and "off" episodes. "On" episodes describe when the medicine is working and symptoms are minimal. "Off" episodes are when the medicine has not yet taken effect or is wearing off and symptoms are worsened. Some of these symptoms are caused by the levodopa wearing off during the day.⁴

Dopamine agonists are less effective on the motor symptoms of PD. However, they have a lower rate of causing dyskinesia. MAO-B inhibitors are less effective than levodopa or dopamine agonists, but they have fewer side effects. Treatment should be customized to each person based on the risks and benefits of the specific drug and stage of disease progression.⁴

Along with medicine, physical therapy can help with muscle cramps. Regular exercise and stretching also help strengthen muscles and maintain flexibility. Assistive devices such as walkers or canes may be helpful.⁴

Surgery to implant a device that provides deep brain stimulation (through electrical impulses) may be an option for some people whose symptoms are not well controlled with medicine. This surgery does not cure or change the course of the disease progression, but it may help with the symptoms of PD.²

Treating the non-motor symptoms of Parkinson’s disease

Besides the motor symptoms, PD can cause a number of non-motor symptoms that affect other brain and body functions, such as:^1,3

• Fatigue
• Gastrointestinal issues, such as constipation
• Urinary issues
• Sleep problems
• Orthostatic hypotension (a drop in blood pressure that occurs upon standing)
• Pain
• Reduced sense of smell
• Mood changes, like depression or anxiety
• Cognitive changes, like, slowed thinking, confusion, or difficulty orienting oneself in familiar locations, or dementia
• Hallucinations, delusions, or paranoia
• Sexual dysfunction
• Weight loss or weight gain
• Vision problems
• Dental problems
• Skin problems
• Impulsive behaviors

Treatments of non-motor symptoms are specific to the symptoms. Some symptoms may be caused as a side effect of medicines used to treat the motor symptoms of PD. Changing these drugs can improve symptoms.³

Other non-motor symptoms may be treated with drugs or other therapies. For example, certain drugs can reduce bladder issues in people who have urinary problems. Pain may be treated with medicines, physical therapy, and exercise. Complementary therapies, such as acupuncture or massage, may also help relieve non-motor symptoms of PD.³

It is important to note that treatments for some non-motor symptoms can interact with PD treatments and cause unwanted or dangerous side effects. It is important that people with PD see a movement disorder specialist who is trained in the use of drugs for PD. They understand drug interactions and how some medicines may make symptoms worse.