Studies have shown that antibody responses to several vaccine antigens were reduced with the use of fever reducer medication before or at the time of vaccination. However, an age-appropriate dose of a non-aspirin-containing pain reliever may be considered for the treatment of fever and local discomfort that might occur following vaccination.

Additional Resources:

Study: Effect of prophylactic paracetamol administration at time of vaccination on febrile reactions and antibody responses in children

MMWR: Recommendations of the Advisory Committee on Immunization Practices (ACIP)