Vaccines_Acetaminophen_immune response_A nurse administers a vaccine on a patient's shoulder

The truth about acetaminophen’s effects on vaccines

Some people believe taking an over-the-counter fever reducer before a vaccine disrupts the body’s immune response, but that may be false
August 20, 2019

No one enjoys getting vaccines, but most of us do it anyway. “Vaccines are absolutely crucial to keep yourself, your children and those around you healthy,” said Katie Hepfer, DNP, C-PNP, clinical assistant professor at the Texas A&M College of Nursing. “Most health care providers know immunization schedules can be overwhelming to parents of young children. However, it is so important to keep yourself and your children up-to-date with your vaccinations.”

That advice leaves many parents—and even adults going to get the shot for themselves—wondering if there is a way to make it easier.

What is a vaccine?

A vaccine is made from small amounts of a weak or dead agent that resembles a disease-causing germ, bacteria or virus. “The amount and strength of the disease within a vaccine is so small that it won’t give you the disease. Instead, it will build your immunity against the disease,” Hepfer said. “Unlike most medicines, a vaccine does not treat or cure, but actually prevents illness.”

As Hepfer explained, the purpose of a vaccination is to get your body’s immune system familiar with that disease, so it can build a defense. The agent teaches the body to recognize, destroy and remember those pathogens as foreign to the body. If the immune system learns of a disease in a weakened state through a vaccine before coming into contact with the disease at full strength, it can easily fight it off and keep you healthy.

Common vaccine side effects versus a reaction to a vaccine

“Just like how most medications have side effects, vaccines also have varying levels of side effects,” Hepfer said. “However, for the most part, vaccine side effects are minor and temporary.” Unless your health care provider recommends against a vaccine for you or your child for a health reason, the side effects are not big enough to warrant skipping a vaccine.

The most common side effects from a vaccination are pain, swelling and redness at the injection site. You or your children may also notice a mild fever as well as general soreness on the arm or leg of the injection.

“There is a difference between a common side effect and an allergic reaction to a vaccination,” Hepfer said. “An allergic reaction may be a rash, difficulty breathing or even something more severe. If that happens, you need to contact your health care provider. However, if you notice an elevated temperature, which is a common side effect, it is generally nothing to be concerned about.”

Hepfer notes an elevated temperature after a vaccination is actually a good thing. It means your immune response is working.

Acetaminophen does not impact the immune response

Often, people elect to take an over-the-counter pain reliever, or give one to their children, prior vaccines to help with the side effects. “Remember a vaccination can cause an initial pain during the injection, but also soreness and an elevated temperature afterwards,” Hepfer said. “For many people, it makes sense to take acetaminophen as it both relives pain and reduces temperature.”

The discussion about acetaminophen’s impact on immunity comes with the fever-reducing effect. Typically, fevers are a sign your body is working to kill a virus. As a result, many people worry an over-the-counter drug that reduces fevers will impact how well your body fights the viral agents from a vaccine.

Hepfer said not to worry. “The research does not support this belief,” she said. “We have little reason to believe that acetaminophen impacts the body’s natural immune response when getting a vaccine. If taking acetaminophen before a vaccine makes you feel better, do it. However, I always recommend waiting until you notice pain or fevers before taking a medication like acetaminophen or ibuprofen.”She notes many of the common vaccine side effects like fevers and soreness do not appear immediately after the injection. They appear several hours later. “If you take a pain reliver prior to a vaccination, it will likely wear off before the side effects appear,” Hepfer said. “However, some people take a pain reliver before, some take one after and others do neither. Any of these options are okay as long as you and your child get vaccinated.”

A tip to make getting a shot easier

Getting immunized can be a point of anxiety for both adults and children. Luckily, Hepfer gave some simple advice applicable to both adults and children to overcome the fear. She recommends distraction. “If it a child is getting a shot, hold them in a comforting way or give them a toy or distraction item,” Hepfer said. For adults, she recommended a game on your phone or listening to music. “Do not underestimate the power of distraction.”

— Mary Leigh Meyer

You may also like
Woman in a pool
Top summertime illnesses and injuries
Dr. James Samuel holds up a petri dish to take a close look at pathogens
Texas A&M testing COVID-19 vaccine candidates for iBio, Inc.
Helping others make healthy choices
female family nurse practitioner student uses stethoscope to check heart and lung sounds on Hispanic pediatric patient
$1.5 million grant to establish academic-practice partnership with rural health care providers