Cardiovascular Safety of Metoclopramide Compared to Domperidone: A Population-Based Cohort Study

BACKGROUND

Metoclopramide and domperidone are common prokinetics used to alleviate gastrointestinal symptoms. However, both drugs may trigger ventricular arrhythmias.

AIM

We conducted this population-based study to compare the 30-day cardiovascular safety of metoclopramide versus domperidone in outpatient care.

METHODS

We used health care databases to identify a cohort of patients in Ontario, Canada newly dispensed metoclopramide or domperidone. Inverse probability of treatment weighting based on propensity scores was used to balance the baseline characteristics of the two groups. All outcomes were assessed in the 30 days following drug dispensing. The primary outcome was hospital encounter with ventricular arrhythmia. The secondary outcomes were hospital encounter with cardiac arrest, all-cause mortality and cardiovascular mortality.

RESULTS

We identified 196,544 patients, 19% of whom were prescribed metoclopramide. There was no difference in the risk of a hospital encounter with ventricular arrythmia (0.02% in both groups), or cardiac arrest (0.10% with metoclopramide and 0.08% with domperidone). However, 1.34% of patients died after starting metoclopramide compared to 0.52% of patients starting domperidone; weighted risk ratio 2.50 (95% confidence interval [CI] 2.13 to 3.03). Similarly, 0.42% of patients died of cardiovascular causes after starting metoclopramide compared to 0.19 % of patients starting domperidone; weighted risk ratio 2.00 (95% CI 1.44 to 2.77).

CONCLUSION

The 30-day risk for a hospital encounter with ventricular arrhythmia was low for both metoclopramide and domperidone, with no significant difference in the rate between the two drugs. The higher 30-day risk of death observed with metoclopramide compared with domperidone in this study has also been observed in other studies and warrants further investigation.

[Self-medication among patients admitted to the emergency department of Kinshasa University Hospital]

A cross-sectional descriptive study was conducted at Kinshasa University Hospital (KUH) to determine the prevalence of self-medication among patients admitted to KUH and to identify commonly used drugs. 391 patients aged 14 to 92 years admitted to the KUH emergency department between 15 January and 15 February 2011 were included in the study. 233 patients out of a total of 391 (59.6%) used self-medication between the onset of symptoms and the visit to KUH. The number of drugs used ranged from 1 to 7. Of the 233 patients who practiced self-medication, 224 (96.1%) used pharmaceutical drugs alone, 4 (1.7%) used traditional African remedies alone, 1 (0.4%) used Chinese medicine alone, and 4 (1.7%) combined pharmaceutical drugs with traditional African remedies. Analgesics and antipyretics (44.3%), non-steroidal anti-inflammatory drugs (NSAIDs) (26.3%), antimalarials (20.6%) and antibacterials (12.3%) were the most commonly used pharmaceutical drugs. Paracetamol was the most commonly used analgesic and antipyretic (89.1%). Among NSAIDs, diclofenac (65%) was the most widely used. Artemisinin-based combination drugs (40.4%) were the most commonly used antimalarials, with lumefantrine being the most common. The most widely reported antibacterials were betalactam antibiotics (ampicillin and amoxicillin) (42.9%). The results show that self-medication, based mainly on commonly prescribed pharmaceutical drugs, appears to be a common therapeutic option before seeking hospital care and may be a major threat to individual and community health.