MOSES LAKE — Medical professionals say it’s not dangerous and it doesn’t happen to many people, but it does happen. And it’s common enough that it’s got a name – “COVID arm.”

As the name implies, it’s one of the many knock-on effects of the COVID-19 pandemic. In this case, it’s a reaction to getting vaccinated, according to a post on the U.S. Centers for Disease Control and Prevention website.

The CDC website characterized COVID arm as a “red, itchy, swollen or painful rash” on the arm where the patient got the COVID-19 shot.

The rashes might not be visible at once; they can start a few days to more than a week after the first shot and sometimes cover large portions of the arm, according to the CDC website post.

The reaction is most often associated with the Moderna vaccine, but there are more rare instances with the second dose of the Pfizer-BioNTech shot, according to a recent case report by the National Institutes of Health. There were no reports of this side effect with the Johnson & Johnson vaccine.

A post on the Healthline website listed some specific symptoms, including a red rash that can spread down the arm, itching, swelling and a hard lump under the skin at the injection site. It will not escalate to a serious allergic reaction, according to the Healthline post.

A post on the Cleveland Clinic’s website said the immune system is working a little too hard. It’s a reaction of the immune system, a component of the vaccine, specifically the protein in it, as an infection. The immune system works to fight off what it reads as a possible threat, which the Cleveland Clinic characterized as an “over-exuberant response.”

People who have experienced COVID arm should still get the second shot, according to the CDC. It might be necessary to get the second shot in the other arm, something patients should discuss with the medical professionals at the location where they’re getting the vaccine.

COVID arm usually goes away within three to five days, according to the Cleveland Clinic. In the meantime people can treat the swelling with a cold pack or cold compress. The itching can be treated with antihistamines, the CDC website said. Over the counter medications like acetaminophen or a “non-steroidal anti-inflammatory drug” like ibuprofen are recommended for pain.

Cheryl Schweizer can be reached via email at [email protected].