Vaccines were developed as a permanent solution to certain diseases, including tetanus, chickenpox, and flu. These are typically a dose of the active viruses and microorganisms that can develop acquired immunity against infectious diseases.

Similar to drugs, some side effects have been noticed after vaccines were administered to patients. According to Victoria state’s Better Health Channel, the frequency of these side effects is one to ten in a hundred immunized people.

People of different ages may experience different symptoms, and at varying levels of severity. These side effects aren’t usually life-threatening, but require adequate knowledge to know when to consult a doctor.

Here are five side effects people may experience after getting a vaccine:

Guillain-Barre Syndrome

Shortened as GBS, this syndrome is an autoimmune disease that causes the body’s immune system to work counteractively against the nervous system. Its symptoms vary in severity and include swallowing difficulties, eyesight problems, tingling sensations, and deteriorating coordination.

This condition can progress relatively fast, such as within the first two weeks of noticing the initial symptoms of the disease. This can cause the eventual death of certain patients. Health professionals advise that if you notice the combination of the said symptoms, you should get medical attention immediately.

This disease’s primary cause is widely unknown, but some of the identified triggers include trauma, hepatitis A, B, C, E, HIV, Zika virus, flu, and flu vaccines. Read more about GBS and its association with vaccines here.

Swelling And Redness Around Vaccine Shot

Redness occurs when some individuals receive a vaccine shot due to skin sensitivity. After the vaccine is administered, there’s usually a mild irritation, which results in skin redness.

This is accompanied by mild irritation and swelling. These reactions usually last between two and seven days. Doctors recommend that you seek medical attention when you notice an allergic reaction. This is because these symptoms can be an indicator of a more serious problem.

If you think you’re allergic to ingredients such as formaldehyde and aluminum salts, talk to your doctor or pharmacist about getting a flu shot that doesn’t contain any of those ingredients.

In some cases, a doctor may recommend that you get a flu shot through a nasal spray. This contains only the actual virus, and none of the ingredients that cause an allergic reaction. However, nasal sprays don’t always provide complete protection.


Fever is another common vaccine side effect. This symptom may start within several hours after the vaccine was administered, and will go away after some days without intervention.

The severity of the fever depends on your body’s immune system, but it requires further medical attention if it persists for more than three days.

In fewer cases, the vaccine-induced fever is due to an allergic body reaction to the vaccine. Allergies are common among children, but adults may also suffer from them in rare instances. Other side effects associated with vaccine-induced fever are restlessness, drowsiness, and loss of appetite.

Muscle And Joint Aches

People who have weak immune systems or allergies may experience muscle pains after receiving a vaccine. The muscles can also experience temporary swelling, accompanied by skin redness.

Other symptoms include back, thigh, and neck pains. The swelling caused by the muscle pain may last from a few hours to a few days, depending on the muscle pain severity.

To help alleviate muscle pains caused by a vaccine injection, it’s recommended to rest for three hours after receiving injections. The injection spot will heal within a couple of weeks, and all the symptoms will be eliminated. 

Fatigue And Headache

It’s not uncommon for people to complain of tiredness after taking a vaccine. According to Medical News Today, this is a natural body response to use all available energy to build its immunity.

Also, the Center for Disease Control And Prevention (CDC) estimates one out of four recipients will experience tiredness.

Headache and fatigue are closely associated, and vaccine recipients may develop headaches after getting a vaccine. Medical doctors don’t consider this pair of side effects life-threatening, and they only prescribe pain relievers to combat the headache.


Vaccines provide the necessary prevention to certain infectious diseases, but they also come with side effects. The rarest side effect is Guillain-Barre Syndrome, which affects the nervous system of vaccine recipients.

Redness and swelling around the vaccine injection point is the commonest side effect of vaccines. Fever is identified as a possible side effect in persons with allergic reactions.

Muscle and joint aches can also develop after vaccine administration. Lastly, fatigue and headaches can also develop as the body overworks itself to build up its immune system.