Mouthwash is a liquid oral hygiene product designed to rinse the mouth, freshen breath, and help control plaque and gingivitis. It serves as an adjunct to regular brushing and flossing. While beneficial for oral health when used as directed, mouthwash is explicitly not intended for ingestion. It contains various ingredients that can be harmful if swallowed, ranging from mild irritation to serious toxicity depending on the amount consumed.
Common Ingredients and Their Effects
Mouthwashes contain a variety of active ingredients, each with a specific purpose for oral care. Ethanol, or ethyl alcohol, is present in many formulations, typically ranging from 5% to 27% by volume, and acts as an antiseptic to kill bacteria. Fluoride, commonly sodium fluoride, is included to strengthen tooth enamel and prevent cavities. Essential oils like menthol, eucalyptol, and thymol provide a fresh taste and contribute to the product’s antiseptic properties.
Other antimicrobial agents, such as chlorhexidine gluconate and cetylpyridinium chloride (CPC), are also found in some mouthwashes to reduce plaque and manage gum disease. Methyl salicylate is used for flavor and mild pain relief, while hydrogen peroxide may be included for whitening and bacterial reduction.
Consequences of Accidental Swallowing
Accidentally swallowing a small amount of mouthwash, such as a residual sip after rinsing, is a common occurrence. For adults and older children, this is generally not considered harmful. Common, milder symptoms might include an upset stomach, nausea, or a brief burning sensation in the mouth or throat. Some individuals may also experience temporary diarrhea.
These effects are typically mild and transient, resolving on their own. The body can usually process small, diluted quantities of these ingredients without significant systemic impact.
Serious Risks of Larger Ingestion
Consuming larger quantities of mouthwash, whether accidentally or intentionally, can lead to more severe health issues due to the concentrated ingredients. Mouthwash containing ethanol can cause intoxication similar to alcoholic beverages, potentially leading to alcohol poisoning. Symptoms of ethanol toxicity include nausea, vomiting, drowsiness, dizziness, and confusion, and in more severe cases, coma or slowed breathing. The alcohol content in some mouthwashes, such as Listerine, can be higher than many beers and wines.
Fluoride, while beneficial for teeth in small amounts, can cause toxicity if ingested in larger quantities. Acute fluoride ingestion may result in nausea, vomiting, diarrhea, abdominal pain, and electrolyte imbalances. In extreme cases, it can affect kidney and heart function. Ingredients like methyl salicylate can lead to rapid-onset salicylate poisoning, potentially causing brain swelling, seizures, or cardiac arrest. Other compounds, such as phenolic compounds found in some mouthwashes, can contribute to severe metabolic acidosis and multiorgan system failure in massive ingestions.
Immediate Steps After Ingestion
If mouthwash has been swallowed, it is important to assess the amount ingested and the individual’s symptoms. For small, accidental amounts, rinsing the mouth with water is advisable. Drinking a small amount of milk or water can help dilute any remaining chemicals in the digestive tract. It is generally not recommended to induce vomiting, as this can cause further irritation or lead to aspiration of the mouthwash into the lungs.
If a larger amount of mouthwash has been consumed, particularly by a child, or if severe symptoms develop, immediate medical attention is necessary. Contacting a poison control center is the recommended first step for expert guidance. In the United States, the national, toll-free Poison Help line is 1-800-222-1222, available 24 hours a day. When calling, be prepared to provide details about the type of mouthwash, the estimated amount swallowed, and any observed symptoms.