An adjuvant is classically defined as “an ingredient of a vaccine that helps create a stronger immune response in the patient’s body.”
The most commonly used adjuvant in vaccines in the United States is aluminum.
Aluminum is an adjuvant in many DTaP, hepatitis A, hepatitis B, Hib, HPV, pneumococcal, and Tdap vaccines.
Monophosphoryl lipid A is another adjuvant that is used in one brand of HPV vaccine.
Not all vaccines have adjuvants though. And other countries use different adjuvants.
The bottom line is that adjuvants in vaccines are safe.
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