Cough syrup can cause diarrhea as a side effect. This is a common concern for those seeking relief from cough and cold symptoms. While generally safe, certain components can interact with the digestive system, leading to loose stools.
How Cough Syrup Can Affect Digestion
Many cough syrups contain sugar alcohols like sorbitol, mannitol, and xylitol, often used as artificial sweeteners in “sugar-free” versions. These are poorly absorbed in the small intestine. They travel to the large intestine, drawing water into the bowel through osmosis, which can lead to a laxative effect and diarrhea. Consuming more than 20-50 grams per day can cause gastrointestinal discomfort, though individual tolerance varies.
Other inactive ingredients (excipients) in cough syrups may also contribute to digestive upset in some sensitive individuals. These include certain preservatives or dyes, which, while generally recognized as safe, could irritate the gastrointestinal lining. The likelihood and severity of diarrhea depend on the specific cough syrup formulation, dosage, and individual sensitivity. Higher than recommended doses of active ingredients, such as guaifenesin, can also cause gastrointestinal side effects like stomach upset, nausea, vomiting, stomach pain, and diarrhea. However, these are rare at standard doses.
Managing Diarrhea and When to Seek Medical Advice
If you experience diarrhea after taking cough syrup, consult a healthcare professional about stopping or reducing the medication dosage. Maintaining adequate hydration is important to counteract fluid loss. Drinking plenty of clear liquids like water, clear broths, and electrolyte solutions can help prevent dehydration.
Adjusting your diet can also help manage symptoms. Opt for bland, low-fiber foods such as bananas, rice, applesauce, and toast, often referred to as the BRAT diet. Avoid foods that can worsen diarrhea, including fried or greasy foods, high-fiber foods like bran, and beverages with caffeine or alcohol. Monitoring the frequency and severity of diarrhea is important to assess if symptoms are improving.
Seek medical attention if diarrhea is severe, lasts over two days, or if you show signs of dehydration like excessive thirst, dry mouth, reduced urination, weakness, or dizziness. Other warning signs include severe abdominal or rectal pain, a fever of 102°F (39°C) or higher, or bloody or black stools. For infants and young children, seek medical attention if diarrhea doesn’t improve after 24 hours, if there are no wet diapers for three or more hours, or if they show unusual sleepiness or irritability.