DNA Explainer: Why does your arm hurt after getting the COVID-19 vaccine?

Getting a sore arm is one of the most common side effects that people report after getting their COVID-19 vaccine shot. For some, the pain lasts for more than a day. Many even need some treatment to reduce the discomfort like cool compression, over-the-counter medicines and basic arm exercises. People have even put up their ordeals on social media, sharing their plight with others.

But why does the COVID-19 vaccine make the arm hurt? Here’s a quick explanation of what ‘the sore arm after the jab’ is all about.

What is your body telling you?

As per medical experts, a sore arm after the COVID -19 vaccine is a sign that your body is reacting as it should. Your immunity is working as expected.

There are a number of COVID-19 vaccine side-effects that have been documented in jab receivers across the globe. A side-effect literally means that your immune system is performing the job it is supposed to. They can and do impact our daily activities and quality of life for a short while. Nevertheless, these symptoms are harmless and eventually go away.

The most common side effects people are getting after the COVID-19 vaccine are soreness, redness or swelling in the arm at the spot you get the jab, headache, fatigue, muscular pain, fever, chills and nausea.

For some, these side effects are worse with the second shot, compared to the first one. But that’s normal and you can feel good that your immunity is in place.

What causes the sore arm?

The COVID-19 vaccines are given via intramuscular injections. This means it is directly injected into the arm muscle. Generally, it’s the deltoid muscle which is the large muscle giving helping the shoulder with its range of motion.

The vaccine triggers inflammation at the site where the shot is administered. This suggests your immunity is being activated. The site of needle insertion is also an injury spot, although a tiny one.

Our bodies fight off infections using a variety of mechanisms. Our immunity tries to break down bacteria, viruses and dead cells. It produces antibodies that then attack the debris left behind after the break down. pieces of the virus left behind by the macrophages. Our immunity also attacks our own cells that have been infected.

What the vaccines do is they “trick the immune system.” Our body thinks there is a real virus which it needs to quickly remove. Experts explain the soreness in the arm with the analogy of a battlefield.

The arm is the site of a full-fledged war between our white blood cells and the vaccine’s immunity activating components.

How long will the soreness last?

It can take a few days for your body’s reaction to the jab to calm down. This is the reason some may experience soreness in their arm for some time. Similarly, the pain from the tiny injury might also take a while to go away.

While lesser in magnitude, this soreness similar to the pain experienced when one twists a knee or an ankle. Muscle pain can take a few days to subside.

There are ways to make it better. Keep your arm moving to stimulate blood flow to the area which helps reduce soreness. You can apple some cool compress to ease the pain. You might have some discomfort with the sleeping posture for a day or two. But remember, soreness in the arm is a good sign and the pain will eventually go away.