People with Parkinson’s disease may experience involuntary movements such as tremors, which can occur in the muscles of the face. Medication can also cause involuntary movements that affect the mouth.

Parkinson’s disease affects the control of body movements and can cause involuntary movements. In certain cases, these affect the face and mouth.

In Parkinson’s disease, nerve cells in the brain experience damage or die. These cells can no longer produce the chemical dopamine, which is important for controlling movement.

This article will explore the involuntary mouth movements that can occur in people with Parkinson’s disease, why they occur, treatment, and more.

An older person applying lip balm to their lips. People with Parkinson's disease experience involuntary mouth movements.Share on Pinterest
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People with Parkinson’s disease experience involuntary movement changes throughout the body. These may include:

Taking Parkinson’s medications over a long period may also lead to involuntary movements. These can affect speech, chewing, and facial expressions and may involve:

  • twisting of the neck
  • grimacing
  • tongue and lip movements
  • difficulty with swallowing

Facial tremors

Tremors affecting the face are relatively uncommon in Parkinson’s disease. One study found that only 5% of participants with the condition exhibited facial tremors. Another study identified facial tremors in 18.1% of participants with Parkinson’s disease.

Researchers believe that the risk of lip and jaw tremors increases among people who have had Parkinson’s disease for longer. It may also be more common among females and older individuals.

Parkinson’s disease can also cause stiffness in facial muscles. The lips of individuals who experience this may lack any sign of movement, known as facial masking.

Learn more about Parkinson’s tremors and how they differ from other tremors.

Jaw movements

Similarly, involuntary movements and stiffness can affect the jaw in people with Parkinson’s disease.

Individuals experiencing involuntary jaw movements may develop altered chewing patterns. Those with jaw rigidity may experience a reduced range of motion while chewing or speaking.

Involuntary tongue movements

Some people with Parkinson’s disease experience tongue movements they cannot control.

These can affect speaking and swallowing and make it difficult to chew food, as the tongue may expel it from the mouth.

Involuntary movements in and around the mouth can cause a range of symptoms, including:

  • Teeth knocking: Some people may experience knocking of their teeth due to facial tremors.
  • Involuntary opening and closing of the jaw: This can lead to difficulty with speech and eating.
  • Side-to-side tongue movements: These may also cause difficulty with eating or speaking.
  • Incomplete opening of the mouth: In certain cases, jaw rigidity can make it difficult to open the mouth fully.
  • Involuntary lip movements: These can affect speaking patterns.
  • Reduced facial expressions: Lip rigidity can also weaken lip muscles and reduce the range of facial expressions a person can make.

Although involuntary mouth movements are not as common as some other signs of Parkinson’s disease, they may impact the quality of life for people with this condition who experience them.

Learn more about other symptoms of Parkinson’s disease.

Although there is currently no cure for Parkinson’s disease, many treatments are available to help manage its symptoms.


The most effective medication for Parkinson’s disease is levodopa, which goes under the brand name Sinemet (carbidopa/levodopa). This drug may help reduce movement symptoms associated with this condition.

However, levodopa can also cause involuntary movements affecting the jaw, lips, or tongue. Some individuals taking levodopa for Parkinson’s disease may develop involuntary mouth movements due to their treatment.

Exercise and physical therapy

Certain forms of exercise that may help with movement symptoms include:

Exercise and physical therapy may help a person manage Parkinson’s symptoms without the side effects associated with other treatments.

Other treatment options

Some individuals with Parkinson’s disease may benefit from deep brain stimulation (DBS), in which surgeons place a pulse-generating device under the skin of the chest or stomach, connected to one or two fine wires that surgeons insert into specific brain areas.

The device delivers high frequency stimulation that may change electrical signals in the brain that cause Parkinson’s symptoms.

Researchers are also looking into vagus nerve stimulation (VNS) as a treatment. Similar to DBS, this involves using a device to stimulate certain brain areas in an effort to reduce symptoms. A surgeon can implant this device within the brain. However, noninvasive forms of VNS are also available.

Vibrotactile stimulation devices are another potential treatment for involuntary movements. They deliver vibrations to different muscles in the body. These devices may help reduce tremors and other involuntary movements.

Because no single treatment works best for everyone with Parkinson’s disease, it is best for individuals experiencing involuntary mouth movements to speak with a healthcare professional. They can help design an appropriate treatment plan specific to each person.

Learn more about treatment options.

Several medications may help address involuntary movements, such as:

Tips when starting new medications

Before beginning a new medication, it is best to speak with a medical professional about proper dosage and timing. Parkinson’s disease medications can also cause side effects that may include:

When beginning a new medication, keeping a diary and noting any physical changes or side effects can be helpful. If any negative side effects occur, it is best to consult a healthcare professional as soon as possible.

Doctors advise that anyone experiencing new or worsening Parkinson’s disease symptoms contact a healthcare professional.

Muscle stiffness, tremors, changes in walking patterns, and speech changes are all common symptoms. New or worsening mouth movements may also be important for healthcare professionals to know about.

It is also best for individuals who develop negative side effects from Parkinson’s medications to seek medical advice. Although many side effects are minor, levodopa can cause severe side effects such as hallucinations or psychosis.

Parkinson’s disease can cause involuntary muscle movements that may affect the face and mouth. Movements affecting the mouth can occur in the jaw, tongue, or lips.

Although these movements are less common than other Parkinson’s disease symptoms, they may negatively affect a person’s quality of life if they do occur. Involuntary mouth movements may affect speech, chewing patterns, and facial expressions.

Experts recommend that individuals experiencing new or worsening involuntary mouth movements contact a healthcare professional. Effective treatment may help people with Parkinson’s disease manage these and other symptoms.