Flu Vaccine Side Effects
Allergic reactions to the flu shot are very rare. Symptoms of an allergic reaction can include
- problems with breathing,
- hives,
- wheezing,
- pale skin,
- a rapid heart rate, and
- dizziness.
Vaccines are medications that boost our ability to fight off certain diseases. Many of the vaccine-preventable diseases are highly contagious and even fatal in non-immunized individuals (Table 1). Prior to the development of vaccines, these diseases disabled or killed millions of people. Many people living in developed countries today do not appreciate the value of immunizations because the successful use of vaccines has almost eradicated many of these diseases. These diseases are still dangerous and can kill people who are not adequately protected from them.
Anthrax |
Cervical cancer |
Diphtheria |
Haemophilus influenza type B (Hib) |
Hepatitis A |
Hepatitis B |
Human papillomavirus (HPV) |
Influenza (flu) |
Japanese encephalitis (JE) |
Lyme disease |
Measles |
Meningococcal disease |
Monkeypox |
Mumps |
Pertussis (whooping cough) |
Pneumococcal disease |
Poliomyelitis (polio) |
Rabies |
Rotavirus (severe diarrhea) |
Rubella (German measles) |
Shingles |
Smallpox |
Tetanus (lockjaw) |
Varicella (chickenpox) |
Yellow fever |
Immunization is the act of receiving a vaccine. Immunity is the ability of the body to recognize specific infecting organisms as foreign and thereby protect against them.
Allergic reactions to the flu shot are very rare. Symptoms of an allergic reaction can include
Immunity (protection) can occur one of two ways:
There are two major categories of vaccines.
Measles |
Mumps |
Rubella |
Vaccinia |
Varicella |
Zoster |
Yellow fever |
Rotavirus |
Oral polio |
BCG |
Oral typhoid |
Diphtheria |
Tetanus |
Polio shot |
Hepatitis A |
Hepatitis B |
Rabies |
Influenza shot |
Pertussis |
Acellular pertussis |
Human papillomavirus |
Anthrax |
Typhoid shot |
Cholera |
Pneumococcus |
Meningococcus |
Salmonella |
Haemophilus influenza type b |
Simultaneous administration (vaccines given at the same visit but not in the same shot) of most commonly used vaccines does not decrease the response to the vaccines or increase the risk for adverse reactions. The simultaneous administration of vaccines was instituted to increase compliance with recommended immunization schedules. If people have to come back many times to get additional shots, there is an increased chance that they will not get all recommended vaccinations. In children, there are now a few combination shots that contain multiple vaccines in a single shot. Most of these are approved for use in adults, except Tdap (a three-vaccine combination) and one containing measles/mumps/rubella (MMR). There is an ongoing controversy in the public media about giving "too many" vaccines at one time to little children. Physicians, however, do not believe that children are at risk from "too many" vaccinations given at one time.
There is no such thing as a risk-free vaccine. However, the health risk of not being vaccinated is real and is clearly greater than that of being vaccinated. Most side effects from vaccinations are mild and limited to local reactions at the injection site and/or a mild fever. Unfortunately, there are rare serious and even fatal side effects related to vaccines. While these events are sad, not taking the vaccine could also result in death or disability.
In December 2017, the American College of Allergy, Asthma, and Immunology published an updated guideline and recommended that patients with egg allergy receive the influenza vaccine. Even though the vaccine is currently manufactured in eggs, there is only minimal egg protein in the vaccine. There is no increased risk of reaction in patients with egg allergy.
With this new recommendation to utilize the routine influenza vaccine in patients with egg allergy, there is no need to utilize the egg-free vaccine that was released in 2013. Therefore, although the recombinant hemagglutinin influenza vaccine (RIV) is not made using eggs, it is no longer needed.
Most reactions to vaccines are mild and self-limited. These are usually limited pain, swelling, and redness at the site of the vaccination. These occur in up to 80% of individuals and start within hours of the vaccination. Some people can get more generalized symptoms, including fever, muscle aches, headache, loss of appetite, and feeling generally tired. These systemic (generalized) reactions are seen more commonly with live attenuated vaccines and usually occur seven to 21 days after the vaccine was given. The worst (and very uncommon) reaction is anaphylaxis (a severe allergic reaction). These reactions usually occur shortly after the vaccine is given and can be life-threatening. Fortunately, these reactions only occur two times for every million doses of vaccine given.
There are two types of contraindications (reasons not to give a vaccine): permanent and temporary.
Women who are pregnant should not receive the MMR, oral typhoid yellow fever, varicella, or zoster vaccines. These vaccines are made from live attenuated viruses and potentially could cause a problem. Pregnant women may receive tetanus and influenza vaccines as needed. It is safe to receive hepatitis A & B, meningococcal, and pneumococcal vaccines.
Vaccination should not be postponed for any of the following reasons:
By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.
The side effects of most vaccines are mild and go away with in a few days. Common side effects of many vaccines include soreness at the injection site, low-grade fever, fatigue, headache, and muscle aches. However, some vaccines can have serious or even life-threatening reactions. Thousands of lives are saved for every serious side effect that is caused. The specific side effects of specific vaccines are found at https://www.cdc.gov/vaccines/vac-gen/side-effects.htm.
Vaccine-preventable diseases are indeed infrequent in the United States because of the success of the vaccine program. However, if people stop receiving vaccines, these diseases will come back rapidly. This occurred with measles in the early 1990s and resulted in many deaths.
If the reaction is a mild reaction with just some injection-site tenderness, low-grade fever, fatigue and headache, then simply taking a dose or two of acetaminophen (Tylenol) may be helpful. The use of ibuprofen or other nonsteroidal anti-inflammatory drugs has been discouraged because of the concern that these drugs might decrease the immune response after the vaccine (make the vaccine less effective). Studies are still ongoing at this time. It is best to check with the physician who ordered the vaccine if you are concerned about the symptoms or you want to take something for the symptoms.
If you think you are having a serious side effect, consult your physician immediately. If a person is seriously injured by a vaccine, there is available compensation through the National Childhood Vaccine Injury Act.
In 1986, the United States government set up the National Childhood Vaccine Injury Act. This act provides a "no fault" compensation mechanism for people injured by vaccines.
Health care workers are treated a little differently than other adults for two reasons. First, a health care worker is more likely to be exposed to certain risks of infection (such as hepatitis B) than the normal population. Second, if a health care worker becomes infected, they may transmit those infections to their patients (chickenpox, pertussis).
There are a number of vaccines that are not routinely given in the U.S. that are recommended for foreign travel. Which vaccines a person needs completely depends on the country to which he or she is traveling. The CDC has a web site that is constantly updated with recommendations for vaccines (https://wwwnc.cdc.gov/travel/). People can learn about recommended vaccines by simply navigating to the country they plan to visit. These vaccines can then be obtained from many local health departments or travel clinics.
Travelers going to sub-Saharan Africa and tropical South America are required by International Health Regulations to have yellow fever vaccination. All other vaccines are simply recommended to protect the traveler. Common vaccines given for foreign travel include hepatitis A vaccine, hepatitis B vaccine, and typhoid vaccine. U.S. citizens who have not received their recommended (routine) vaccinations (Tdap, MMR, polio, etc.) should make sure that they get all routinely recommended vaccines before traveling. Many of these diseases are still very common in other parts of the world. For instance, people going to Mecca on the Haj are required to be vaccinated against meningitis.
Health Solutions From Our Sponsors
Genital warts is a sexually transmitted infection (STI, STD) caused by the human papillomavirus (HPV). It is the most common STD in the US. The warts can appear anywhere on the skin where sexual contact has occurred.
The warts look like raised, flesh-colored lumps or bumps that have a cauliflower-like appearance. Signs and symptoms of genital warts in women include vaginal, vulva, or groin pain, itching, and burning where the wart(s) is.
Treatment can remove warts or lesions, but it does not prevent spread of the virus, and the warts usually grow back. Removing genital warts does not prevent the infection from spreading elsewhere on the body.
There is no cure for genital warts, and there is no vaccine to prevent them; however, there is a vaccine to prevent infection from four common types of HPV. Gardasil vaccine available for female adolescents and teens to prevent HPV infection and cervical cancer.
Headaches can be divided into two categories: primary headaches and secondary headaches. Migraine headaches, tension headaches, and cluster headaches are considered primary headaches. Secondary headaches are caused by disease. Headache symptoms vary with the headache type. Over-the-counter pain relievers provide short-term relief for most headaches.