Nasal regurgitation is the involuntary backflow of food or liquid from the throat into the nasal cavity during swallowing. Though often alarming, this occurrence is a symptom of a failure in the swallowing mechanism. This happens because the pharynx, the muscular tube connecting the mouth and nose to the esophagus, is not properly sealed off. Understanding why this seal fails is the first step toward addressing the issue, which can range from a simple mechanical error to an underlying medical condition.
The Normal Swallowing Process
Swallowing (deglutition) is a complex, rapid sequence of muscle contractions that moves a food or liquid bolus from the mouth to the stomach. Precise coordination ensures the bolus enters the esophagus and not the airway or nasal passage. The pharyngeal phase specifically manages the risk of nasal regurgitation.
This phase relies heavily on the velopharyngeal sphincter, a muscular valve formed by the soft palate and the pharyngeal walls. As the bolus moves backward, the soft palate elevates and contracts against the back walls of the throat. This creates a tight, momentary seal that closes off the nasopharynx, preventing food or liquid from traveling upward into the nose and directing it toward the esophagus.
Temporary and Acute Causes of Nasal Regurgitation
Occasional nasal regurgitation is often due to a temporary disruption in the rapid coordination of swallowing muscles. A common trigger is a momentary loss of muscle control caused by sudden actions like laughing, coughing, or sneezing while food is in the throat. These actions can cause the soft palate to relax or move to its breathing position, opening the nasal passage during the swallow.
Certain beverages can also mechanically trigger this event. Highly carbonated drinks contain dissolved carbon dioxide gas, which can cause a sudden burp or rapid gas expansion in the throat after swallowing. This upward pressure can force liquid past a momentarily unsealed velopharyngeal sphincter.
Temporary muscle discoordination can also be a side effect of certain medications that cause xerostomia (dry mouth). Antihistamines, antidepressants, and muscle relaxants are common examples that reduce saliva production or depress the central nervous system. A lack of saliva makes it difficult to form a cohesive bolus, and impaired nerve signaling can weaken the muscle contractions necessary for a complete pharyngeal seal.
Underlying Medical Conditions Affecting Swallowing
Frequent or chronic nasal regurgitation often signals a persistent issue, generally categorized as velopharyngeal insufficiency (VPI) or oropharyngeal dysphagia. VPI means the soft palate cannot form a complete seal due to structural or functional problems. Structural defects, such as a congenital cleft palate, post-surgical changes (e.g., following a tonsillectomy), or excessively large tonsils, can physically prevent the soft palate from reaching the pharyngeal wall.
Neurological disorders are a major cause, as they impair the nerve signals coordinating the complex swallowing reflex. Conditions like stroke, Multiple Sclerosis (MS), Parkinson’s disease, and Amyotrophic Lateral Sclerosis (ALS) can weaken the muscles of the soft palate and throat. Parkinson’s disease, for instance, can lead to hypokinetic dysarthria, characterized by reduced range and speed of muscle movement, weakening the velopharyngeal seal.
Generalized muscle weakening disorders, such as Myasthenia Gravis, can cause the soft palate muscles to fatigue rapidly during a meal, leading to seal failure. Chronic gastroesophageal reflux disease (GERD) can also cause inflammation and irritation in the pharynx, impairing the precise timing and coordination required for a proper swallow. In these cases, the failure of the velopharyngeal mechanism is consistent and requires medical intervention.
Diagnosis and Management
When nasal regurgitation is frequent, a healthcare provider, often an ear, nose, and throat (ENT) specialist or a speech-language pathologist (SLP), determines the underlying cause. Diagnosis begins with a clinical swallow evaluation and progresses to instrumental assessments to visualize the swallowing process directly. The Modified Barium Swallow Study (MBS), also known as a videofluoroscopic swallow study (VFSS), is a dynamic X-ray procedure.
During an MBS, the patient swallows foods and liquids mixed with barium, which appears on X-ray. This allows the clinician to observe the entire swallow in real-time. Fiberoptic Endoscopic Evaluation of Swallowing (FEES) is another tool involving a thin, flexible camera passed through the nose to view throat structures during the swallow. These studies confirm the exact nature of the seal failure, whether due to muscle weakness, structural deficits, or timing errors.
Management strategies vary widely based on the diagnosis. For muscle weakness or poor coordination, the SLP may prescribe specific swallowing exercises and compensatory strategies.
Swallowing Exercises
The Effortful Swallow involves squeezing the throat muscles hard during the swallow to increase pharyngeal pressure.
The Mendelsohn Maneuver requires the patient to hold the larynx at its highest point during the swallow for several seconds, which helps increase the duration of upper esophageal sphincter opening.
Compensatory Strategies
Postural adjustments, such as the chin-tuck, are taught to protect the airway and reduce regurgitation. If the cause is structural, surgical intervention may be necessary to repair the soft palate tissue to ensure complete velopharyngeal closure.