Published on: 3/17/2025
Slight drooling from one side of the mouth can occur when the nerves or muscles on that side do not manage saliva as well as on the other side, which may happen in early or mild neurological disorders.
When you swallow, your brain sends strong messages to your mouth muscles to help move saliva into your throat. Sometimes, the nerves on one side may not work perfectly together with the muscles, and this can cause a little extra saliva to leak out. This slight drooling on one side could be due to a very small imbalance in how the nerves control the muscles that help with swallowing. In some conditions, like early stages of Parkinson’s disease, changes in brain signals can affect these processes so that one side might clear saliva less effectively. Research shows that disruptions in the brain’s connections can lead to drooling because they change how the muscles work. Even if it is just slight and only on one side, it can be a sign that the nerves and muscles need a little extra help. If this drooling starts bothering you or if you notice other symptoms, it might be helpful to talk with a healthcare provider who can check your swallowing and nerve function.
(References)
Polychronis S, Nasios G, Dardiotis E, Messinis L, Pagano G. Pathophysiology and Symptomatology of Drooling in Parkinson's Disease. Healthcare (Basel). 2022 Mar 11;10(3):516. doi: 10.3390/healthcare10030516. PMID: 35326994; PMCID: PMC8951596.
Iorgulescu G. Saliva between normal and pathological. Important factors in determining systemic and oral health. J Med Life. 2009 Jul-Sep;2(3):303-7. PMID: 20112475; PMCID: PMC5052503.
Huang T, Tang LL, Zhao JY, Shang SA, Chen YC, Tian YY, Zhang YD. Drooling disrupts the brain functional connectivity network in Parkinson's disease. CNS Neurosci Ther. 2023 Oct;29(10):3094-3107. doi: 10.1111/cns.14251. Epub 2023 May 5. PMID: 37144606; PMCID: PMC10493659.
We would love to help them too.
For First Time Users
We provide a database of explanations from real doctors on a range of medical topics. Get started by exploring our library of questions and topics you want to learn more about.
Purpose and positioning of servicesUbie Doctor’s Note is a service for informational purposes, and the provision of information by physicians, medical professionals, etc. is not a medical practice. The provision of information by physicians, medical professionals, etc. is not a medical treatment. If medical treatment is required, please consult your doctor or medical institution. We strive to provide reliable and accurate information, but we do not guarantee the completeness of the content. If you find any errors in the information, please contact us.