En español | If you're experiencing common side effects such as a headache, fever or chills after receiving the COVID-19 vaccine, it's perfectly fine to take an over-the-counter pain reliever such as ibuprofen or acetaminophen to relieve your discomfort, experts say.
But don't take those medications before you get your shot, unless advised to do so by your doctor, because you could dampen the effectiveness of the vaccination, said Gregory Poland, M.D., an infectious disease expert at the Mayo Clinic in Rochester, Minnesota, and director of Mayo's vaccine research group.
The U.S. Centers for Disease Control and Prevention (CDC) also advises against the use of pain relievers before vaccination “for the purpose of preventing post-vaccination symptoms.”
Tell the CDC About Your Side Effects
Health officials are tracking side effects with an easy app called v-safe you download to your smartphone. Once you get your first dose, your health care provider will give you information about how to get started. The daily survey takes only about 30 seconds, Poland said, and it gives health officials important safety information.
The recommendation stems from a few small studies, mostly on children, that found taking pain relievers before getting a vaccine decreased the immune response, Poland said, meaning your body might have a harder time recognizing and fighting off the coronavirus in the future. Poland notes that the research on the topic is limited and results have been inconsistent. Still, he and other experts say, it's best to err on the side of caution.
If you take a pain reliever regularly for a chronic condition like arthritis, you may want to skip it the morning before you receive the vaccine, Poland said, but talk to your doctor first. If it's a medication you can't get through the day without, you're probably better off taking it, he said.
Side effects can be more severe after second dose
Adults age 55 and older typically have fewer side effects than younger people, but you may still feel under the weather for a few days after your vaccine.
"It means your body is doing what you asked it to do,” said Buddy Creech, M.D., an infectious disease specialist and director of the Vanderbilt Vaccine Research Program in Nashville, Tennessee.
Expect more side effects after the second dose. In addition to a sore arm, common symptoms include tiredness, headache, muscle pain, joint pain, chills and fever, according to the CDC.
Dean Blumberg, M.D., an infectious disease specialist at UC Davis Health, pointed out two other post-vaccine symptoms doctors have been seeing: a rash or itchiness around the injection site that arises five to 10 days after vaccination — sometimes referred to as “COVID arm” — and swollen lymph nodes under your arm.
How to treat vaccine side effects
- Fever/chills/muscle pain
If you have a fever but it's not bothering you much, you don't have to do anything to treat it, the doctors said. If you're very uncomfortable, go ahead and take acetaminophen (Tylenol) or a nonsteroidal anti-inflammatory drug (NSAID) such as ibuprofen (Advil or Motrin).
"I felt pretty bad the day after with chills and muscle aches, and I can't imagine not taking Tylenol or Motrin that day,” Creech said. Also drink plenty of fluids and dress lightly, the CDC advises.
Call a doctor if your fever lasts more than a few days or it's paired with other symptoms, such as a cough and sore throat.
Blumberg had just a mild headache after his second dose, but he said some of his colleagues who also got the vaccine have described pounding headaches that were more like migraines. “Bright lights bothered them. They just wanted to stay in a dark room,” he said.
Again, pain relievers should help, he said, and get plenty of rest.
If you're tired, don't feel bad about spending the day in bed, Creech said. “I'll tell you, the more we vaccinate, the more we realize fatigue is a real part of this,” he said.
A nap can help you feel better, he said, as can a brisk walk or other exercise. And if you're one of those people who don't like to sit still, you won't hurt yourself if you decide to push through the fatigue, he said.
Fortunately, in most people, the tiredness lasts for only a day or two.
- Pain, swelling or a delayed rash at the injection site
Almost everyone has some arm soreness after vaccination. Using or exercising your arm can help ease pain, the CDC says. The agency also recommends applying a cool, wet washcloth over the area.
Blumberg said some patients are reporting a delayed rash or redness that appears five to 10 days following immunization. The area may be swollen, red or itchy, he said. In the Moderna clinical trial, 0.8 percent of participants reported delayed injection site reactions.
Infectious disease doctors believe it's a mild allergic reaction, Blumberg said. Treat it with an over-the-counter antihistamine such as Benadryl or a topical steroid such as hydrocortisone.
- A lump in your armpit
If you have a lump in your armpit or just above your collarbone, it's probably a swollen lymph node, Blumberg said. CDC data show that 12 to 16 percent of clinical trial participants reported swelling somewhere besides the injection site.
The swelling may last a few weeks, he said. “It's a normal part of your immune system response, but sometimes it can be uncomfortable,” Blumberg said. “There's nothing you need to do for it. Eventually, it will go away.”
Michelle Crouch is a contributing writer who has covered health and personal finance for some of the nation's top consumer publications. Her work has appeared in Reader's Digest, Real Simple, Prevention, The Washington Post and The New York Times.