From Gov.Uk drugsafety document (sorry long c+p!)
Advice for healthcare professionals
Indication
•Domperidone is now restricted to use in the relief of nausea and vomiting
•It should be used at the lowest effective dose for the shortest possible time
Contraindications
•Domperidone is now contraindicated in people:
•with conditions where cardiac conduction is, or could be, impaired
•with underlying cardiac diseases such as congestive heart failure
•receiving other medications known to prolong QT interval or potent CYP3A4 inhibitors
•with severe hepatic impairment
•Patients with these conditions should have their treatment reviewed at their next routine appointment and be switched to an alternative treatment if required
Posology
Oral formulations
•For adults and adolescents over 12 years of age and weighing 35 kg or more, the recommended maximum dose in 24 hours is 30 milligrams (dose interval: 10 milligrams up to three times a day)
•In children under 12 years of age and weighing less than 35 kg, the recommended maximum dose in 24 hours is 0.75 mg/kg body weight (dose interval: 0.25 mg/kg body weight up to three times a day)
Suppository formulation
•Suppositories should only be used in adults and adolescents weighing 35 kg or more, the recommended maximum daily dose in 24 hours is 60 milligrams (dose interval: 30 milligrams twice a day)
Duration of treatment
•The maximum treatment duration should not usually exceed one week
•Patients currently receiving long-term treatment with domperidone should be reassessed at a routine appointment to advise on treatment continuation, dose change, or cessation
Administration of liquid formulations
•Oral liquid formulations of domperidone should only be given via appropriately designed, graduated measuring devices (eg, oral syringes for children and cups for adults and adolescents) to ensure dose accuracy
Additional advice for pharmacists:
Non-prescription availability of domperidone:
Pharmacists are asked to take the following steps when supplying domperidone without prescription:
•Ask questions to exclude supply for people for whom domperidone is contraindicated (see above)
•Advise people to take domperidone only for nausea and vomiting–it should no longer be taken for bloating and heartburn
•Advise people to take the lowest dose for the shortest possible time up to a maximum daily dose of 3 tablets and for a maximum period of 48 hours
Advice to give to patients
•Domperidone should only be used for short periods of time to treat nausea and vomiting
•Speak to your doctor or pharmacist at your next routine visit if you are taking domperidone and have any problems with your heart or concerns about your treatment
•Seek medical attention immediately if you experience heart-related symptoms such as irregular heartbeat or fainting while taking domperidone