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How long does it take for the flu vaccine to work?


There is no exact answer for how long it takes for a flu vaccine to start working. The exact time it takes for a vaccine to reach its full effect varies for every individual. However, it generally takes about two weeks for your body to generate a sufficient amount of antibodies to protect you from the flu. During the first two weeks after receiving your vaccine you are still susceptible to the flu and it is still possible to catch the flu despite the flu vaccine.

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Answers to questions regarding information about medications or health conditions are not for diagnostic or treatment purposes and are not conclusive as to the presence or absence of any health condition. Consult your physician for diagnosis and treatment of your medical condition. The information provided is not a substitute for medical advice. Advances in medicine may cause this information to become outdated, invalid or subject to debate. Professional opinions and interpretations of the scientific literature may vary. Walgreens' terms of use and general warranty disclaimer apply to all services provided. If you are in need of immediate medical attention, contact your physician, poison control center or emergency medical professional. If you need to speak with a pharmacist for non-emergency matters, contact your local Walgreens pharmacist or call a pharmacist toll-free at 1 (877) 250-5823.

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