Does Metoprolol Cause Diarrhea?
Yes, metoprolol can cause diarrhea in approximately 5% of patients taking the medication, according to FDA drug labeling. 1
Evidence from Drug Labeling
The FDA-approved drug label for metoprolol clearly lists diarrhea as a known adverse effect:
- Diarrhea occurs in about 5 out of 100 patients taking metoprolol 1
- It is listed among the gastrointestinal adverse reactions for oral metoprolol treatment
- Other gastrointestinal side effects include nausea, dry mouth, gastric pain, constipation, flatulence, and heartburn (each occurring in about 1% of patients)
Clinical Significance and Management
Risk Assessment
Diarrhea from metoprolol is:
- Relatively common (5% incidence)
- Generally mild and transient
- Rarely severe enough to require discontinuation
Management Options
When diarrhea occurs in a patient taking metoprolol:
Evaluate severity:
- Mild to moderate: May resolve with continued use
- Severe or persistent: Consider medication adjustment
Treatment approaches:
- For mild cases: Symptomatic management with hydration and dietary modifications
- For moderate cases: Consider antidiarrheal medications (loperamide, diphenoxylate-atropine)
- For severe cases: Medication dose reduction or switching to an alternative beta-blocker
When to discontinue:
- Persistent diarrhea causing dehydration
- Significant weight loss
- Severe impact on quality of life
Differential Considerations
It's important to rule out other causes of diarrhea in patients taking metoprolol:
- Concurrent medications (especially if recently started)
- Gastrointestinal infections
- Underlying gastrointestinal disorders
- Dietary factors
Clinical Context
While diarrhea is a recognized side effect of metoprolol, it's worth noting that:
- Beta-blockers as a class can cause various gastrointestinal symptoms
- The incidence of diarrhea with metoprolol (5%) is higher than some other common side effects
- Patients should be informed about this potential side effect when starting the medication
- In most cases, the benefit of metoprolol for cardiovascular conditions outweighs this potential side effect
When diarrhea occurs in a patient taking metoprolol, the medication should be considered as a possible cause, especially if the onset correlates with starting or increasing the dose of the medication.