Propranolol and Gastrointestinal Upset
Yes, propranolol can cause upset stomach and gastrointestinal symptoms, including nausea, vomiting, epigastric distress, abdominal cramping, diarrhea, and constipation, as documented in the FDA prescribing information. 1
Common Gastrointestinal Side Effects
The FDA drug label explicitly lists the following gastrointestinal adverse reactions associated with propranolol: 1
- Nausea and vomiting
- Epigastric distress (upper abdominal discomfort)
- Abdominal cramping
- Diarrhea
- Constipation
Clinical Evidence and Context
Diarrhea is a recognized common adverse effect of propranolol therapy, particularly in pediatric populations treated for infantile hemangiomas, where it ranks among the most frequently reported side effects alongside sleep disturbance and cold extremities. 2
Case reports have documented severe diarrhea requiring drug discontinuation. In one documented case, a patient experienced diarrhea and weight loss on propranolol 20 mg four times daily, which resolved upon discontinuation and recurred upon rechallenge at the same dose. 3
Mechanism and Management Considerations
The gastrointestinal effects of propranolol likely relate to its non-selective beta-blockade affecting gut motility and splanchnic blood flow. Research demonstrates that propranolol reduces gastric mucosal perfusion in patients with portal hypertension, which may contribute to gastrointestinal symptoms. 4
Food interactions can modify propranolol absorption and potentially affect tolerability. Protein-rich meals increase propranolol bioavailability through reduced hepatic extraction, which may influence the severity of side effects. 5
Clinical Recommendations
When patients report gastrointestinal upset on propranolol: 2, 1, 3
- Consider dose reduction if therapeutic effect can be maintained at lower doses
- Administer medication after meals rather than on an empty stomach, which may improve tolerability
- Hold doses temporarily if the patient develops vomiting or diarrhea (this is particularly important to prevent hypoglycemia)
- Monitor for severe complications such as mesenteric arterial thrombosis or ischemic colitis, though these are rare 1
Important Caveats
While gastrointestinal symptoms are common, more serious gastrointestinal complications are rare but documented, including mesenteric arterial thrombosis and ischemic colitis. 1 Any patient with severe or persistent abdominal pain, bloody diarrhea, or signs of acute abdomen requires immediate evaluation.
The occurrence of new diarrhea in any patient receiving propranolol should prompt consideration of an adverse drug reaction rather than assuming an alternative etiology. 3