Coronavirus vaccination: The reason why your arm hurts after getting the COVID-19 vaccine

There are many COVID-19 vaccine side-effects that are mild and reactogenic in nature. Most of these tend to resolve on their own, but seldom could be troublesome, based on their intensity. Pain in the arm, and soreness is one such side-effect.

Post-vaccination, the site of injection- where the vaccine is administered can turn sore, pain or sometimes even swell up due to inflammation. It is also one of the most common vaccine side-effects reports across the world and takes the longest to resolve. The inflammatory side-effect can be so extreme for some, it has been actually referred to as 'COVID arm'.

ALSO READ: How to minimize COVID-19 vaccine side-effects at home

But what makes it so dreaded? Are there ways to minimize it? We explain...

Side-effects with a vaccine can show up in a number of ways- mostly in the form of systematic and inflammatory reactions. With most people who do get vaccinated, pain in the arm where you get jabbed, or experiencing soreness, stiffness, difficulty in moving the arm around could be common reactions.

Even so, the numbness and the pain caused vis-a-vis injections could be temporary, the side-effects could throw people off their normal routines and be disturbing, it can be intriguing to wonder what causes it in the first place.

Pain and tenderness at the site of injection are actually one of the first side-effects that kick in when you get the vaccine jab. It also is part of the localized response when you get vaccinated, i.e. the effects which kick in at the exact spot where the jab is given.

The reaction that causes arm soreness is an example of how the body first perceives the vaccine to be. When you do get the shot, the body considers it to be an injury, much like a bleed or a cut and sends immune cells to the arm and relaxes the blood vessels. As a part of the process, the immune cells also cause inflammation, which later helps you protect against the same pathogen if you ever encounter it again. This is what experts call a 'reactogenicity' of the vaccine. Some of the arm irritation also comes from the muscle reacting to the small amount of vaccine liquid that was injected into the arm.

Apart from soreness, some people can also experience redness, irritation and swelling near the injection site. A COVID arm, which has been associated with mRNA vaccines particularly, is an extention of the soreness and can result in itchy, swollen patches on the arm.

Most vaccination side-effects tend to last for 2-3 days and the same exists for arm soreness post-vaccination. However, if you probably experience more inflammation, or tend to be more sensitive to pain, the soreness could stretch for upto 5 days post-vaccination.

However, having said this, if the pain does not subside a week after vaccination, a checkup with a doctor would be advisable.

The tenderness and soreness are directly linked to how inflamed your arm is. Put simply, the more inflammation you have, the more swollen and probably painful your arm could be- signifying the reason why some people experience more intense, or longer-lasting pain at the site of injection than others.

However, many experts also add that extreme soreness in the arm, or tenderness could also be a prime sign that your vaccine is working just as well, as it is supposed to be. A vaccine is supposed to prompt inflammation in the body and create antibodies. If you do experience high levels of inflammation, it probably is a good sign that your vaccine is doing its job well and working to provide ample protection.

When the vaccine is injected onto the arm, the most common reaction is felt at the site where the vaccine jab is given, and inflammation happens, which ultimately causes soreness and pain. However, it can also be common to experience some level of pain, ache and discomfort in the arm that has been jabbed, since vaccination side-effects also tend to cause muscle aches, stiffness and malaise. The pain and discomfort people say can be similar to what happens when you develop a flu-like illness.

Soreness experienced with the vaccine injection can be highly discomforting and take a while to recover from. In some cases, it could almost render the arm immovable for at least a couple of days.

That being said, there are definite ways to minimize or alleviate the intensity of your arm soreness and recover from the side-effect speedily. Most experts recommend people use therapeutic measures such as an ice pack, warm/hot water compress at the site of injection to minimize soreness and inflammation. Taking Epsom salt baths could also help relieve pain.

Some pain relievers can also be taken to fight inflammation and pain, post-vaccination. However, taking them preemptively, or before your scheduled vaccination may not be so helpful, and not really advised by doctors.

Apart from this, there are also some other ways to combat this side-effect. Exercising, basic stretching and incorporating movements to reduce stiffness in the arm can definitely help. However, do remember to not overdo your efforts and go slow.