What to Expect After Your COVID Vaccine
It’s common — and normal — to have some minor side effects after your shots. Learn which symptoms show up most often and what to do about them

Here’s one side effect of the COVID-19 vaccine you might actually look forward to: a feeling of elation. “When I got my first shot, I was walking on air,” says Robert Hopkins, M.D., chair of the National Vaccine Advisory Committee to the U.S. Department of Health & Human Services. He is happy to report that the only other side effect he experienced was mild soreness at the injection site, similar to that from other types of shots. Dr. Hopkins, who is also a professor and director of general internal medicine at the University of Arkansas for Medical Sciences, hopes that his experience can inspire fellow Arkansans to also get immunized.
Admittedly, this is an uphill battle: About half of the state’s residents typically skip a flu shot, and in a Pew Research Center survey from early December, 39% of Americans said they probably wouldn’t get a COVID-19 shot either, citing concerns about safety and the speed of the vaccines’ development. That could be a problem for all of us: We need as many people as possible to roll up their sleeves in order to reach herd immunity.
The good news is that half of the people in that 39% group said they’d consider getting the shot once they saw how it went for other people. It’s normal to have questions; after all, these are unprecedented times. One way to ease your mind is to learn exactly what might happen and why. Our primer on vaccine side effects may be just what the doctor ordered.
9 Common Side Effects of COVID-19 Vaccines
First, let’s cover why vaccine side effects happen in the first place. Vaccines work by tricking your body into thinking it has an infectious disease and thus needs to build up antibodies to fight it off. Some vaccine-related side effects can be thought of as “good news”: They mean that your immune system has recognized the “fake” invader and started assembling an antibody army.
Almost always, the physical effects of vaccines are much milder than those caused by the disease itself. Indeed, most people in the clinical trials for the Moderna, Pfizer/BioNTech, and Johnson & Johnson vaccines reported similar side effects, and in general, those symptoms were mild, manageable, and short-lived. The following were the most common:
- Redness, swelling, and/or pain at the injection site
- Tiredness or fatigue
- Headache
- Muscle pain
- Chills
- Joint pain
- Fever
- Nausea and/or vomiting
- Swelling of the lymph nodes near the injection site
Timing and duration: Side effects usually start within a day or two after vaccination and go away in a few days’ time. For those who get the two-dose vaccines (Moderna or Pfizer/BioNTech), side effects seem to be more common after the second dose.
Easing discomfort: To soothe arm soreness, apply a cool, wet washcloth to the area, and try moving your arm around — it can help with pain and swelling. If you develop a mild fever, dress in lightweight clothing and drink plenty of fluids. Over-the-counter medicines (like acetaminophen or ibuprofen) may help, too.
Effects on daily life: Most side effects reported by study participants did not affect their ability to go about their usual day. And researchers found that side effects were less frequent and less severe among people over age 55. Some people did feel tired, achy, and feverish for a day or two, so you may want to time your doses for when you’re less busy and have time to rest. But remember, even if you don’t feel great after getting the shot, “You cannot get COVID from the vaccine,” Dr. Hopkins says. Neither the Moderna nor the Pfizer/BioNTech vaccines contain the “live” virus or even a complete copy of a “dead” virus.
That said, if you do develop symptoms of COVID-19 around the time of your shot, it’s possible you were exposed to the virus right before your injection or before you developed immunity (which takes a few weeks). Symptoms of COVID-19 include:
- Dry cough
- Chest pain, or shortness of breath
- Loss of taste or smell
- Painful, itchy lesions on hands and/or feet (“COVID toes”)
- Eye problems such as light sensitivity, bloodshot eyes, swollen eyelids, watering, and discharge
- Confusion (especially in older people)
None of these are considered common side effects of the vaccine, so if you have them, call your health care provider and get a COVID-19 test.
If You Do Have an Unusual Side Effect, Report It
About 70,000 people participated in Phase 3 trials for the Moderna and Pfizer/BioNTech vaccines, and by the end of Febraury, more than 64 million people in the U.S. received their first dose, according to the Centers for Disease Control and Prevention (CDC). Now the government’s goal is to vaccinate 150 million Americans by the end of April. With that many recipients, we could see new (albeit rare) side effects show up in the general public that weren’t reported in the trials. Case in point: Three patients with dermal fillers (anti-aging facial injections) experienced some swelling near the fillers after getting the Moderna vaccine. The reactions were quickly resolved with steroids and/or antihistamines. In addition, about 21 people had a severe (but not fatal) allergic reaction to ingredients in the shot; they all were treated and quickly recovered.
The more we know about any new or unusual side effects, the better prepared we can be to keep everyone safe. If you experience an unexpected side effect after your COVID-19 vaccine, here are two ways to report it:
- CDC’s V-safe after-vaccination health checker app
- CDC/FDA Vaccine Adverse Event Reporting System (VAERS)
If that seems like a pain, consider this: The sooner we conquer the coronavirus, the sooner we can come together at restaurants, sports arenas, wedding venues, graduation parties and concert halls. And thanks to these vaccines, we’re this close! No wonder Dr. Hopkins was walking on air.
The information in this story is accurate as of press time and posting. To limit the spread of the coronavirus, it’s important to continue practicing social distancing (keeping at least 6 feet away from people outside your household) and washing your hands frequently. You should also be appropriately masked any time you’ll be in public. According to the CDC’s latest guidance means layering a disposable surgical mask underneath a snug-fitting cloth mask or placing a mask fitter over your cloth mask to ensure a tight fit. Because the situation surrounding COVID-19 continues to evolve, we encourage readers to follow the news and recommendations for their own communities by using the resources from the CDC, WHO, and their local public health department.