15 Side Effects of Flu Shots

It takes 14 days for a flu vaccine to become fully active. A small percentage of people who get the vaccine develop a low-grade fever of 101 degrees or less. It is possible that your immune system is aggressively responding to the vaccine.

The flu shot is an intramuscular injection, which means the needle is inserted straight into the muscle tissue. This causes microscopic injuries to the muscular cells. Ten to 64 percent of people who get intramuscular injections experience muscle aches in their upper arms or pain at the injection site.

If you notice increased swelling or redness or endure discomfort in your arm after receiving the flu vaccine, you're experiencing what immunologists call a topical reaction. This is a telltale sign that your immune system functions well. However, if you experience extreme swelling at the injection site or any facial swelling, seek immediate medical attention because you may be allergic to the vaccine.

There is a lot of misinformation about the influenza vaccine. There aren't any active viruses in the shot, so there's no way you can get the flu from the jab. This misconception probably comes from the fact that most people get the flu shot during flu season; an individual may have already contracted the infection before administration of the vaccine.

It's very rare for someone to be allergic to the influenza shot. Anaphylaxis is the allergic response that can cause wheezing, difficulty breathing, the excessive swelling of the mouth and eyelids. Symptoms of allergic reactions include paleness, an outbreak of hives or rash, an increased heartbeat and general weakness. The symptoms occur within a few minutes to a few hours which require medical intervention.

Different strains of influenza produce different symptoms and side effects. The primary types of the flu virus are A, B, and C. Type A flu viruses are the worst of the lot and cause the most harm; they are capable of mutating and defeating the current vaccines. H1N1 or swine Flu is a type A flu virus. Type B flu, a weaker strain of influenza, mainly affect children and the elderly. Type C flu viruses are common, and symptoms are comparable to the common cold.

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It is possible that the flu jab will cause nausea or an upset stomach. Again, immunologists believe this is due to the body's robust immune response to the vaccine. The immune system is responsible for fighting off germ invaders like viruses and bacteria. In the course of aggressively protecting you, you may experience discomforts like nausea and fatigue.

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Only a tiny population of people who get a flu vaccine experience fainting or dizzy spells. This is most often due to the fear of getting the injection than the injection itself. If you are belonephobic, don't worry, you're not alone. Warn the medical professional who gives you the shot and make sure you sit down during and following the injection.

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Many side effects experienced from the influenza shot are demonstrations of your immune systems vitality and strength. Immunologists use the term 'regulation' to describe the body's internal and often microscopic balance preventing the immune system from harming beneficial elements. Headaches, soreness, patches of hives, and even a mild temperature are all signs that your immune system is responding to the vaccine appropriately.

Only one or two people per million injected with the flu vaccine contract Guillain-Barre Syndrome (GBS). The condition is more prone to develop during an active flu outbreak than through a flu vaccine injection. 70 percent of all individuals who contract GBS fully recover, though this can take between a few weeks and a few years. GBS damages the nervous system and causes symptoms such as muscle weakness, numbness, and even paralysis. There is no known connection between the disease and the nasal flu vaccine.

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After receiving the flu vaccine, some individuals report a sense of general fatigue. This isn't the overwhelming tiredness associated with the flu itself but rather a mild, transient feeling of needing more rest. It's a gentle reminder that the body is processing the vaccine and building up its defenses. This fatigue usually dissipates within a day or two, and sometimes quicker, after which the individual usually returns to normal energy levels.

For those who opt for a nasal spray version of the flu vaccine, there's a set of unique side effects to be aware of. Some recipients report a runny nose, a mild cough, or even a slight sore throat. These symptoms are mild and short-lived, being minor side effects rather than serious concerns. The side effects are the body's way of adjusting to the vaccine and generally should not be mistaken for the onset of the flu.

Beyond typical muscle aches, some individuals describe a general feeling of being achy or slightly "off" after receiving their flu shot. This sensation is akin to the feeling one gets before a mild cold sets in. It's usually a temporary state, and like other side effects, it's a sign that the body is actively responding to the vaccine and gearing up its immune response.

It's essential to know the specific signs that might indicate a severe allergic response. Symptoms can include difficulty breathing, a sudden onset of hives, swelling around the eyes or lips, or even a rapid heartbeat. These reactions, though rare, require immediate medical attention. Make sure you understand the potential signs of an allergic reaction, and watch for them after any vaccination.

Recent studies have suggested that females might experience certain side effects of the flu vaccine more frequently than males. This isn't to say that one gender is more at risk than the other, but rather that the body's response can vary based on a myriad of factors, including gender. This is a growing area of study that underscores the importance of personalized medicine and understanding individual responses to treatments.