Harm to a child caused by the off-label use of prochlorperazine maleate tablets due to the discontinuation of licensed prochlorperazine mesilate liquid in the UK.

Prochlorperazine is a commonly used medicine to treat nausea and vomiting. The only liquid formulation in the UK was discontinued in November 2022 due to safety concerns. One alternative option available is to use crushed tablets instead. Crushing and mixing tablets in water to produce a liquid is a widespread practice in paediatrics. However, there is often little evidence to support this practice.In this case report, a patient established on liquid prochlorperazine mesilate who was switched to crushed prochlorperazine maleate tablets experienced significant harm. The child's vomiting became uncontrolled and led to multiple healthcare attendances and a prolonged hospital admission. Control was re-established by increasing the prochlorperazine dose to accommodate for loss of drug during preparation. Care should be taken when converting prochlorperazine mesilate liquid doses to crushed prochlorperazine maleate tablets, and the doses used should not be treated as equivalent.
Competing Interests: Competing interests: None declared.
(© European Association of Hospital Pharmacists 2024. Re-use permitted under CC BY-NC. No commercial re-use. Published by BMJ.)