Domperidone

Domperidone – Patient Information for Australian Use

Basic Product Information

Mechanism of Action

In simple terms: Domperidone increases the movement of the stomach and intestines, helping food move through the digestive system more easily. It is also used to help reduce feelings of sickness (nausea) or being sick (vomiting).

For specialists: Domperidone is a peripheral dopamine D₂ and D₃ receptor antagonist. By blocking dopamine receptors outside the brain (mainly in the gastrointestinal tract and the chemoreceptor trigger zone), it accelerates gastric emptying and reduces the sensation of nausea. Unlike metoclopramide, domperidone does not cross the blood–brain barrier appreciably, reducing risk of central nervous system side effects.

Pharmacokinetics

• Absorption: Peak plasma concentrations are reached within 30–60 minutes after oral administration. Bioavailability is about 15% due to first-pass metabolism.
• Metabolism: Metabolised primarily in the liver by CYP3A4 and secondarily by CYP1A2 and CYP2E1 enzymes.
• Elimination: Excreted mainly in the faeces (66%) and urine (31%), mostly as metabolites.
• Duration of action: Effects last about 6–8 hours.
• Half-life: Approximately 7–9 hours.

Domperidone in Everyday Life and Best Practices

Domperidone is commonly prescribed in Australia to relieve symptoms of feeling sick (nausea) and vomiting, and to support gastrointestinal motility (especially in people with slow stomach emptying or gastroparesis). It can be used short-term for adults and children, but ongoing use should be reviewed by your doctor.

• Typical adult dose: 10 mg up to three times a day (maximum 30 mg/day), usually before meals.
• Paediatric dosing: Based on body weight and age; always follow paediatrician’s guidance.
• Forms: Most adults use tablets; oral suspension is available for children and those who cannot swallow tablets.
• Best practice: Take as directed, do not exceed the prescribed dose, and consult your pharmacist or doctor before combining with other medicines.

Dosing in the Morning vs Evening

• Morning dosing: May be more effective for morning nausea or to help start the day if gastrointestinal symptoms are worst on waking.
• Evening dosing: Can help if symptoms occur later in the day, but night dosing is generally avoided due to potential for QT prolongation (heart rhythm warning) during sleep.
• Regularity: Maintaining consistent dosing times (e.g., before main meals) helps achieve best symptom control and reduces risk of missed doses. Use reminders on your phone or pillbox if needed.
• Tip: Avoid taking later than early evening unless specifically recommended by your healthcare provider.

Taking Domperidone with Food or on an Empty Stomach

Domperidone works best if taken 15–30 minutes before meals. If taken after eating, absorption is slower and it might be less effective.

• With food: Meal slows down absorption; efficacy may be reduced.
• Empty stomach: Higher absorption, faster action.
• In the English context: Standard eating habits with 3 main meals are suitable for regular dosing (e.g., before breakfast, lunch, and dinner).

Interaction Warnings

Please inform your pharmacist or doctor about any medicines or supplements you are taking. Domperidone has potentially serious interactions:

Indications for Domperidone Use

Dosing According to Clinical Indications

Safety Profile and Side Effects

• Common (2–10%): Dry mouth, abdominal cramps, mild headache, mild diarrhoea
• Uncommon: Rash, itchy skin
• Rare/Serious:
  • Heart rhythm disturbances (QT prolongation, serious arrhythmia)
  • Allergic reaction (swelling, hives, breathing difficulties – seek urgent help)
  • Extrapyramidal symptoms (very rare with domperidone, but inform your doctor if you notice muscle rigidity/tremor)
• Warnings:
  • Domperidone should not be used in patients with known heart rhythm disorders, moderate or severe liver disease, or alongside medications that can prolong the QT interval.
  • Use the lowest effective dose for the shortest period necessary.

Guidelines for Proper Use – Practical Tips for Australia

1. Always take domperidone exactly as prescribed by your doctor or pharmacist.
2. Take each dose 15–30 minutes before meals and, if needed, before bedtime (unless told otherwise).
3. Do not exceed the recommended daily dose (usually 30 mg/day for adults).
4. Let your doctor/pharmacist know about all your other medicines (including OTC and complementary medicines).
5. Do not use if you have a history of heart rhythm disorders; report any palpitations, fainting, or chest pain immediately.
6. Store domperidone tablets below 25°C, away from moisture and sunlight, and out of reach of children.
7. Dispose of unused medication safely—ask your local pharmacy about Australia’s Return Unwanted Medicines (RUM) project.
8. If you miss a dose, take it as soon as you remember, unless it is almost time for your next dose. Do not double up.

Alternative Treatment Options

• Metoclopramide (Maxolon, Pramin): Another prokinetic, commonly used, reimbursed by PBS; more central nervous system side effects.
• Ondansetron (Zofran): Often preferred for post-chemotherapy or post-surgery nausea; higher cost, less prokinetic activity.
• Cyclizine, Prochlorperazine: Anti-emetics used for motion sickness or vertigo; different side effect profile.
• Non-pharmacological measures: Dietary modifications, ginger, acupressure, smaller or blander meals may help in mild cases.

Comparative overview:
Metoclopramide is usually the first alternative, it is PBS-listed and costs less. It may be less suitable for chronic use due to the risk of movement disorders (tardive dyskinesia). Ondansetron is usually better tolerated in terms of side effects for nausea but is PBS reimbursed only for certain indications (e.g., chemotherapy). No medicine is entirely risk-free; choice depends on your history and prescriber’s recommendations.

Legal, Registration, and Reimbursement Status in Australia

• TGA (Therapeutic Goods Administration): Approved for relief of nausea, vomiting, and certain motility disorders. Prescription-only medicine (Schedule 4).
• PBS/NFZ (Pharmaceutical Benefits Scheme): In 2024, domperidone is not listed on the PBS for most routine indications; use may not be subsidised by the government.
• Prescribing requirements: Medical or nurse practitioner prescription required; repeated supply is subject to review due to safety signals (especially cardiac risks).
• Dispensing: Only from registered Australian pharmacies on valid prescription.

Latest Research and Clinical Guidance (2022–2025)

• Heart safety first: Several recent reviews (e.g., Australian Prescriber 2023) confirm domperidone’s value but highlight its cardiac side effect risk, especially in the elderly and those on other QT-prolonging medicines.
• Lactation use: Despite its off-label use for boosting breast milk, the 2022–2024 joint statement from Australian breastfeeding and paediatric societies warns that benefits must be weighed against rare—but potentially dangerous—cardiac side effects. Specialist supervision is mandatory.
• Prescribing advice: Use the lowest effective dose for the shortest period needed, avoid use in at-risk heart patients, and always review other medications.
• Key reference: Therapeutic Guidelines: Gastrointestinal (2024 update), Australian Prescriber; Australian Medicines Handbook (AMH) 2024 edition.

Availability and Delivery in Australia

Same-day pharmacy delivery may be available in major capital cities for eligible prescriptions. Extra fees apply for after-hours or urgent courier delivery.

Frequently Asked Questions (FAQ)

1. Can I drive while taking domperidone?
   Most people can drive as normal, but if you feel dizzy or drowsy after taking domperidone, avoid driving or operating machinery until you feel well.
2. Is it safe to use domperidone in pregnancy or breastfeeding?
   Domperidone is generally not recommended in pregnancy unless prescribed by a specialist. For breastfeeding/lactation, off-label use should only proceed under specialist supervision due to cardiac risks for both mother and baby.
3. What should I do if I forget a dose?
   Take it as soon as you remember, unless it’s nearly time for the next dose. Do not double up to make up for the missed dose.
4. Are there any foods I should avoid while using domperidone?
   Avoid grapefruit juice and very high-fat meals as they can increase the risk of side effects or reduce the effectiveness of domperidone. Take doses before meals as best practice.
5. Who should not use domperidone?
   People with certain heart rhythm problems, moderate or severe liver disease, or those taking certain other medicines with known interactions should not use domperidone. Always inform your prescriber of your full medical history.

Ask your pharmacist or doctor if you need more information about domperidone, its safe use, or alternatives for your specific health needs. For urgent side effects (chest pain, fainting, rash, severe diarrhoea), seek medical attention immediately.