6 month old patient received an adult dose of Havrix; 6 month old patient received an adult dose of Havrix; This non-serious case was reported by a nurse via call center representative and described the occurrence of overdose in a 6-month-old male patient who received HAV (Havrix) (batch number Z27PB, expiry date 27-AUG-2026) for prophylaxis. On 27-DEC-2024, the patient received Havrix. On 27-DEC-2024, an unknown time after receiving Havrix, the patient experienced overdose (Verbatim: 6 month old patient received an adult dose of Havrix) and adult product administered to child (Verbatim: 6 month old patient received an adult dose of Havrix). The outcome of the overdose and adult product administered to child were unknown. This report is made by GSK without prejudice and does not imply any admission or liability for the incident or its consequences. Additional Information: GSK Receipt Date: 07-JAN-2025 The nurse reported a 6 month old patient received an adult dose of Havrix which led to adult product administered to child and overdose. The vaccine administration facility was the same as primary reporter.