Can Domperidone and Esomeprazole Cause Diarrhea?

Yes, both domperidone and esomeprazole can cause diarrhea, though the mechanism and frequency differ between these medications.

Domperidone and Diarrhea

Diarrhea is a recognized side effect of domperidone, occurring in approximately 12% of patients in clinical practice. 1

In a large single-center cohort of 115 gastroparesis patients treated with domperidone, diarrhea was among the most common side effects reported, alongside headache and tachycardia/palpitations 1
The gastrointestinal effects are related to domperidone's prokinetic properties—it stimulates gut motility as a dopamine D2-receptor antagonist, which can accelerate intestinal transit 2, 3
Despite this side effect, domperidone is generally well-tolerated, with only 12-14% of patients discontinuing treatment due to adverse effects in clinical studies 1

Domperidone is primarily used for treating gastroparesis symptoms (nausea, vomiting, early satiety) at doses of 10 mg three times daily, with maximum dosing of 20 mg three to four times daily 4
The medication improves gastric emptying and increases lower esophageal sphincter pressure, which can affect overall gastrointestinal motility 3
Importantly, domperidone is contraindicated in patients with gastrointestinal obstruction precisely because it stimulates gut motility 2

Diarrhea occurs in approximately 2% of adolescent patients treated with esomeprazole, making it a less common but documented adverse effect. 5

In a randomized, double-blind study of 148 adolescents with GERD receiving esomeprazole 20 or 40 mg daily for 8 weeks, diarrhea was reported in 2% (3/148) of patients as a treatment-related adverse event 5
Proton pump inhibitors like esomeprazole can cause fecal dysbiosis (disruption of normal gut bacteria), which may contribute to diarrhea development 6
In veterinary studies, esomeprazole administration resulted in diarrhea in 27% of healthy dogs when given alone, though this may not directly translate to human incidence rates 6

Esomeprazole alters gastric pH, which can affect the intestinal microbiome and lead to dysbiosis 6
The reduction in gastric acid may allow bacterial overgrowth in the small intestine, potentially contributing to loose stools
Interestingly, concurrent probiotic administration does not appear to mitigate these effects and may actually worsen dysbiosis 6

When both medications are used together, monitor for additive gastrointestinal effects:

The combination may theoretically increase diarrhea risk through different mechanisms (prokinetic effect + dysbiosis)
If diarrhea develops, assess severity using clinical grading (mild, moderate, severe) and evaluate for dehydration 7
For mild diarrhea, symptomatic treatment with oral rehydration may suffice 7
For persistent or severe diarrhea, consider dose reduction or discontinuation of the offending agent 1

Elderly patients are at higher risk for dehydration complications from medication-induced diarrhea and require closer monitoring 7
Rule out other causes of diarrhea including infection, dietary changes, or concurrent medications before attributing symptoms solely to domperidone or esomeprazole 7
The overall benefit-to-risk ratio for both medications remains favorable for their indicated uses, with diarrhea being manageable in most cases 1, 5