What is Sialorrhea?
Sialorrhea is the medical term for excessive saliva in the mouth, which can lead to drooling. Sialorrhea is very common in Parkinson’s Disease, affecting up to 80% of people.
Understanding Your Salivary Glands
You have three major pairs of salivary glands that produce over 90% of your saliva:
- Parotid glands: The largest glands, located near your ears between the jaw and mastoid bone
- Submandibular glands: Located under your jaw
- Sublingual glands: The smallest, located under your tongue
At rest, your body produces about 0.3 mL of saliva per minute, but this can increase to 7 mL per minute when eating. The average person produces 1 to 1.5 liters of saliva daily. Saliva serves important functions: it lubricates your mouth and throat, helps with chewing and swallowing, protects your teeth from decay, and helps you taste food.
Why Does Drooling Happen in Parkinson’s Disease?
Contrary to what many people think, sialorrhea in Parkinson’s disease is usually NOT caused by making too much saliva. In fact, multiple studies have shown that people with Parkinson’s disease often produce LESS saliva than others.
The real problem is a combination of:
1) Impaired swallowing: Someone without Parkinson’s Disease automatically swallows 1 to 3 times per minute, whereas those with Parkinson’s Disease swallow up to 0.5 times per minute. It is this reduction in automatic swallowing that seems to lead to a build up of saliva.
2) Flexed head posture: The forward-leaning posture common in Parkinson’s disease can cause saliva to escape from the mouth.
3) Reduced awareness: You may not notice saliva building up in your mouth as quickly as before.
Non-Medication Strategies
- Chewing sugar-free gum or sucking on hard candy can serve as motor or tactile cues to swallow more frequently.
- Having a handkerchief available to wipe away excessive saliva.
- Swallowing reminders can help prompt a conscious swallow.
- Speech therapy can help improve swallowing function and oral motor control.
Medication Options
Oral Medications:
- Glycopyrrolate (Robinul)
- Sublingual atropine drops
- Ipratropium bromide spray
- Transdermal scopolamine
Important:
People with Parkinson’s often do not tolerate oral medications side effects including blurry vision, constipation, difficulty urinating, rapid heartbeat, confusion, and even hallucinations.
Botulinum Toxin Injections:
Botulinum toxin (commonly known by brand names like Botox, Dysport, Xeomin, or Myobloc) can be injected directly into the salivary glands to reduce saliva production. This works by blocking the nerve signals that stimulate saliva production.
- Botulinum toxin reduces the amount of saliva that your body produces.
- Injections take 3 to 7 days to take effect and last anywhere from 2 to 6 months (3 months on average).
- Botulinum injections are typically given every 3 to 6 months as needed and tolerated.
- Common side effects include minor bleeding, minor swelling, and dry mouth, all of which go away with time (few weeks to short months).
- It is important to have regular dental appointments and do regular dental hygiene to prevent cavities.
- You can stop these injections at any time without long-term consequences.
Author Mick Reedy, MD, is a Movement Disorders Specialist with
Inova Parkinson’s and Movement Disorders Center (IPMDC)