HCP did not report any side effects; female patient was administered an expired dose of the VARIVAX vaccine on 01/20/2025. HCP stated that the VARIVAX vaccine expired on 01/19/2025; This spontaneous report was received from a certified medical assistant (CMA) concerning to a female patient of unspecified age. The patient’s medical history, historical drugs, known drug allergies, concurrent conditions, and concomitant therapies were not reported. On 20-JAN-2025, the patient was vaccinated with an expired dose of varicella virus vaccine live (oka/merck) (VARIVAX) injection, lot #X002100 (expiration date: 19-JAN-2025), administered for prophylaxis (strength, dose, anatomical location, and route of administration were not provided) (Expired vaccine used). However, the health care professional (HCP) did not report any side effects related to the administration of the expired dose of the vaccine and added that it did not have any prior temperature excursions (T.Es). HCP provided limited pertinent information and had no further clarifications to provide.