From the Guidelines
Domperidone can cause significant side effects, including cardiac risks such as QT prolongation and ventricular tachycardia, which necessitate careful consideration and monitoring, particularly in patients with pre-existing cardiovascular conditions or those taking high doses 1. When prescribing domperidone, it is essential to be aware of its potential side effects to ensure patient safety. Some of the common side effects include:
- Headache
- Dry mouth
- Abdominal cramps
- Diarrhea
- Breast tenderness
- Galactorrhea (milk production)
- Menstrual irregularities
- Gynecomastia (breast enlargement in men) due to its effect on prolactin levels
More severe but rare side effects of domperidone include:
- Heart rhythm disturbances, particularly QT prolongation, which can lead to dangerous arrhythmias 1
- Dizziness
- Drowsiness
- Allergic reactions
The recommended starting dose of domperidone is 10 mg 3 times a day, and escalation to 20 mg 4 times a day should be avoided due to cardiovascular safety considerations 1. A single-center cohort study of gastroparesis patients (n = 115) showed that 68% had improvement in symptom scores, although 7% had cardiac side effects requiring drug cessation 1. It is crucial for patients to seek immediate medical attention if they experience concerning side effects, especially heart palpitations, severe dizziness, or allergic reactions.
From the FDA Drug Label
PRECAUTIONS EQUIDONE Gel may lead to premature birth, low birth weight foals or foal morbidity if administered >15 days prior to the expected foaling date. Do not use in horses with suspected or confirmed gastrointestinal blockage, as domperidone is a prokinetic drug (it stimulates gut motility). Use of EQUIDONE Gel may cause a false positive on the milk calcium test used to predict foaling. Significant inhibition of domperidone metabolism may occur when co-administered with drugs such as erythromycin2 and ketoconazole3.
The side effects of domperidone include:
- Premature birth
- Low birth weight foals
- Foal morbidity
- False positive on the milk calcium test
- Potential increased drug exposure when co-administered with certain drugs, such as erythromycin and ketoconazole 2
From the Research
Domperidone Side Effects
- Domperidone has a lower propensity to cause extrapyramidal side effects compared to metoclopramide 3
- Side effects have seldom occurred with therapeutic doses of domperidone 3
- Asymptomatic meaningful QTc prolongation (>450 ms in males, >470 ms in females) was experienced by 9.5% of patients taking 120 mg/day of domperidone 4
- One-third of patients had asymptomatic non-meaningful QTc prolongation 4
- Palpitations or chest pain was reported in 19% of patients without ECG abnormalities or adverse cardiac events 4
- Prolongation of the QTc interval with chronic use of oral domperidone in standard doses has been reported in the literature 5
- Ten patients had prolonged QTc at follow-up ranging from 453 to 509 milliseconds, without any cardiovascular complaints 5
- There was no relationship between prolonged QTc and daily dose of domperidone, body mass index or age 5
- The risk of sudden cardiac death and ventricular arrhythmia was higher with doses greater than 30 mg per day or with concomitant use of inhibitors of the cytochrome P450 isoenzyme CYP3A4 6
- Domperidone is associated with an increased risk of sudden cardiac death and ventricular arrhythmia compared to nonuse 7
Cardiovascular Side Effects
- Two patients (9.5%) taking 120 mg/day experienced asymptomatic meaningful QTc prolongation (>450 ms in males, >470 ms in females) 4
- Prolonged QTc was verified if >470 milliseconds in females and >450 milliseconds in males 5
- Ten patients had prolonged QTc at follow-up ranging from 453 to 509 milliseconds, without any cardiovascular complaints 5
- The risk of sudden cardiac death and ventricular arrhythmia was higher with doses greater than 30 mg per day or with concomitant use of inhibitors of the cytochrome P450 isoenzyme CYP3A4 6
- Domperidone is associated with an increased risk of sudden cardiac death and ventricular arrhythmia compared to nonuse 7
Gastrointestinal Side Effects
- Domperidone effectively alleviates symptoms of chronic postprandial dyspepsia and nausea and vomiting due to a wide variety of underlying causes 3
- Vomiting associated with the administration of moderately emetic cytotoxic drugs is controlled in the majority of patients 3
- The mean severity of vomiting and nausea was improved by 82% and 55%, respectively, with long-term treatment with high doses of domperidone 4
- Seventy-three percent of subjects benefited from treatment with reduced nausea and vomiting 5