What Could Cause Drooling From the Left Side of the Mouth?

Your mouth normally produces saliva that you swallow without noticing. Sometimes, however, if the control of saliva is uneven, this can cause drooling on one side. For example, certain medications may increase saliva production or interfere with proper muscle control in the mouth, leading to drooling, and sometimes this effect can be more pronounced on one side. Additionally, neurological issues like Parkinson’s disease can affect the nerves and muscles on one side of your face, reducing your ability to manage and swallow saliva efficiently. In children, developmental differences and drug-induced sialorrhea (excess saliva production) can also lead to drooling on one side. If the drooling is new, worsening, or accompanied by other symptoms like difficulty swallowing or changes in facial movement, it’s a good idea to speak with a healthcare provider. They can review your medications and check your neurological function to determine if an underlying condition is causing the imbalance and help develop a management plan.