Drooling and Swallowing Difficulties in Parkinson’s Disease

Drooling and swallowing disorders are common among patients with moderate to significant Parkinson’s disease (PD). Some people suffering from PD produce too much or too little saliva, which makes it difficult for them to eat and swallow. Because the neuromuscular deficits in the disease affect the swallowing muscles, an individual experience Esophageal Motility Disorders (causing difficulty swallowing both solids and liquids). These difficulties lead to fear of choking and hence can negatively impact an individual’s quality of life. Such disorders occur in 50-80% of all Parkinson’s cases, particularly in men.

Sialorrhea (Drooling) and Dysphagia (swallowing difficulty) can severely limit the PD patient’s ability to speak clearly, resulting in slurry speech. Several studies have established a direct correlation between the severity of Dysphagia and the severity of drooling. Oropharyngeal Dysphagia can result from Bradykinesia and poor muscle control of the tongue. The dysfunction of the motor control of the tongue contributes to the pathophysiology of Dysphagia, also resulting in drooling.

Options to treat Drooling and Swallowing Difficulties in Parkinson’s Disease

While Speech Therapy addresses swallowing issues, most of the pharmaceutical treatments are directed to reducing salivary secretion. First, treatment should begin by withdrawing medications such as Cholinesterase Inhibitors, Clozapine or Quetiapine that aggravate drooling. An expert can attempt to improve motor symptoms by using Dopaminergic medications or by performing Deep Brain Stimulation (DBS). However, surgical options to treat PD-led Drooling and swallowing challenges are seldom suggested.

Certain exercises could be considered to improve posture as the tendency to stoop forward causes pooling of saliva. Therapists (Physical or Occupational) can instruct on proper sitting techniques and develop cues to keep the patient’s head up so that saliva naturally drains back. Sitting upright also helps saliva go down. Sucking from straw is recommended to avoid choking on fluids.

Speech Therapy

Since same muscles are used in the tongue and throat to make sounds, Speech Therapy can also help PD fighters with improving swallowing function. This is why, apart from improving speech abilities, ST addresses the inability to manipulate food with the tongue and detect food that is stuck in the cheeks due to weak throat muscles.

Speech experts help the patient reduce delayed swallowing reflex and improve the patient’s posture during eating. With proper positioning, feeding techniques, and possible changes in the consistency of food and drink, symptoms like difficulty to swallow, coughing or gagging while swallowing, drooling and lost gag reflex are addressed.  Lip exercises can improve lip seal and help prevent saliva dripping out. Therapists commonly ask their patients to hold a wide smile and then do pucker lips (like someone is to blow a kiss or whistle).

Medication

The groups of medications such as Anticholinergics, Adrenergic Receptor Antagonists, and Botulinum Neurotoxin (BoNT) are prescribed as pharmacological options to treat drooling in PD.

Typically, an increase of Levodopa or Dopa Agonists can improve stiffness and slowness of tongue and lip muscles that are involved in swallowing. In some cases, Levsin may be prescribed to reduce drooling (avoided if severe constipation or extremely slow gut motility is present). Anticholinergic drugs like Artane or Antihistamines may also be used, but cannot be prescribed to someone confused, forgetful or hallucinating.

Healthy Diet

Various studies have indicated that getting adequate nourishment in PD prevents difficulties with swallowing. Because sugary foods increase production of saliva, use of excessive sugar is suggested to be cut from the diet. Hard candy (sugar-free) and sucking on ice chips are sometimes suggested to decrease drooling. Drinking fluids more frequently to ‘wash down’ saliva is also advised, which also helps in decreasing another PD symptom – Constipation.