inappropriate use due to inadvertently administering pentacel rather than tenivac with no reported adverse event; Initial information received on 21-Jan-2025 regarding an unsolicited valid non-serious case received from a Other health professional. This case involves, a 8 years old male patient who received inappropriate use due to inadvertently administered Diphtheria/Tetanus/5 Hybrid Ac Pertussis/IPV(VERO)/HIB(PRP/T) Vaccine [Pentacel (Vero)] rather than Tenivac with no reported adverse event. The patient’s past medical treatment included Pediarix on 11-May-2017 with at 10 months of age. The patient’s past medical history, vaccination(s) and family history were not provided. On 20-Nov-2024, the patient who received inappropriate use due to inadvertently administered 0.5 ml dose (once) of suspect Diphtheria/Tetanus/5 Hybrid Ac Pertussis/IPV(VERO)/HIB(PRP/T) Vaccine Suspension for injection (lot UK044AA, expiry date: 31-Aug-2025) (unknown strength) via intramuscular route in the right deltoid for immunization rather than Tenivac with no reported adverse event (wrong product administered) (latency-same day). Reportedly, Nurse practitioner stated that patient to receive Tenivac as part of his catch-up immunization schedule on 05-Nov-2024, but he was inadvertently administered Pentacel instead. His vaccine schedule was as follows:11-May-2017, at 10 months of age; 05-Sep-2024, at 8 years of age and 20-Nov-2024 – Pentacel (DTaPIPV-Hib) instead of Tenivac (Td). This suspected adverse reaction report is submitted and classified as a medication error solely and exclusively to ensure the marketing authorization holder’s compliance with the requirements set out in the Directive 2001/83/EC and Module VI of the Good Pharmacovigilance Practices. The classification as a medical error is in no way intended, nor should it be interpreted or construed as an allegation or claim made by the marketing authorization holder that any third party has contributed to or is to be held liable for the occurrence of this medication error.