Back to Resources

Vaccines

Find answers to popular questions about vaccines.

Vaccines
  • Question

    How quickly do antihistamines work versus an epinephrine auto-injector?

    Answer

    Antihistamines are typically given orally, and they can take an hour to take effect. Epinephrine is a shot that is injected in the leg muscle, and it works within minutes.

    Epinephrine is a medication that targets and treats the symptoms and triggers of anaphylaxis.

    An antihistamine will block histamine, but histamine is only one of the factors involved in an anaphylactic reaction, so this will not treat anaphylaxis effectively.

    Any delay in treatment of anaphylaxis can increase the risk of hospitalization or death.

    Epinephrine is very safe. You may experience side effects such as increased heart rate, but taking epinephrine when does not put you in any serious danger. If you think you or your child might need epinephrine, go ahead and use it. You’re much better off treating anaphylaxis with epinephrine without delay, than choosing to watch and wait. Don’t want to risk a life-threatening reaction by not administering epinephrine early enough.

  • Question

    What would cause anaphylaxis in a patient receiving their first immunotherapy maintenance shot? It occurred about three minutes after injection. Was it pure chance, could the dose have been too high, or is there some other potential cause?

    Answer

    Anaphylaxis is a rare side effect of immunotherapy, although it is known to happen.

    You should always discuss the risk of anaphylaxis with your allergist prior to initiating immunotherapy.

    Certain factors can increase the risk of adverse reactions to immunotherapy.  These include uncontrolled asthma, a prior history of anaphylaxis to immunotherapy, and receiving shots during the peak pollen season. Additionally, some medications, such as beta blockers and ACE-inhibitors, can make shot reactions more severe when they do occur.  It is important to alert your allergist to any new medications or health changes prior to getting your shot. 

    You should meet with your allergist prior to your next shot to discuss what particular factors, if any, may have contributed to the reaction, in order to prevent it from happening again.  

  • Question

    My friend has severe contact dermatitis, including intermittent fevers up to 103, from overexposure to epoxy while working in a boatyard. Could this be an allergic reaction? He has been treated by a dermatologist with steroid injections and mild antihistamines, but he is not getting better. His symptoms have been severe for several weeks. Would this be better treated by an allergist?

    Answer

    Epoxy resin can cause more than one type of allergic reaction, but a specific patient usually has only one. It would seem that your friend may be having two different types of unrelated allergic reactions. The following is a summary of some medical facts about contact dermatitis and hypersensitivity pneumonitis, which have both been reported in association with epoxy resin. Your friend should completely avoid all exposure to epoxy resin, and should schedule a consultation with an allergist to better diagnose and evaluate his symptoms. A material safety data sheet may help your friend identify potential sources of exposure.

    Contact dermatitis is the most common allergic reaction to epoxy resin and tends to occur when there is skin contact with uncured epoxy resin. While bisphenol A is the main allergen, other components (e.g., epichlorohydrin, diglycidyl ether) may also cause skin irritation. After the epoxy resin hardens, curing can take up to 2 weeks. However, patients who are very sensitive can even react to “cured” products containing epoxy resin. Nitrile rubber or nitrile butyl gloves, in addition to goggles and protective clothing are recommended for avoidance. Epoxy resin is widely used for sporting goods, dental work, and vehicle parts. For patients with dermatitis related to exposure, corticosteroids and emollients are frequently used for treatment. Unfortunately, in sensitive patients, recurrence of dermatitis occurs with re-exposure to epoxy resin.

    Fever is not typically seen with contact dermatitis, but can be one of the symptoms of hypersensitivity pneumonitis or inhalation fever. In both hypersensitivity pneumonitis and inhalation fever, inhaling epoxy fumes or dust results in symptoms within a few hours. Both of these diseases can start with fever, chills, malaise, nausea, headaches and myalgias (muscle pains). While inhalation fever is not associated with lung symptoms, hypersensitivity pneumonitis is associated with cough, chest tightness, and shortness of breath. Hypersensitivity pneumonitis can develop into a very serious chronic lung disease. when hypersensitivity pneumonitis is present, the allergist is likely to find abnormalities on physical exam, chest x-ray, labs, and pulmonary function studies. If either of these two conditions are diagnosed, the patient should strictly avoid exposure to epoxy resin.

  • Question

    I had an egg allergy when I was a kid, around 5-6 years old. Now I’m 33 and no longer seem to have any reaction to eggs. I would like to get a flu shot, but I’ve been told I need to be sure I don’t have an egg allergy. I eat eggs every morning and don’t notice any reaction, so I don’t think I’m allergic anymore. Can I just get the flu shot? What do you suggest?

    Answer

    If you are tolerating eggs daily without symptoms, you are no longer allergic to eggs. If you do not have any skin, stomach, swallowing, throat, or breathing symptoms related to eating eggs; then you do not have to worry about egg allergy. You should get the influenza vaccine annually, and you do not need any special precautions or monitoring. 

  • Question

    I thought the flu vaccine changed every year, but my nurse looked at this year’s flu vaccine and found it has H1N1 in it. Isn’t that the same as swine flu?

    Answer

    Your nurse is right! The terminology is a little confusing, so here’s a refresher: H1N1 is a subtype of Influenza A that has caused roughly half of all human flu infections we’ve seen in the past several years.

    H1N1 viruses are identified by two surface proteins: Hemagglutinin (H) and Neuramidase (N). The strains H1, 2 and 3, and N1 and 2 are found in people – a lot more strains are found in birds and pigs, and can be spread to humans. If a sufficient genetic shift occurs in an animal virus strain, it can then be transmitted person to person.

    Scientists closely monitor the strains infecting humans as well as animals, since crossover to humans may signal the next pandemic influenza.

    Yes, the human influenza strains do shift from year to year, but it is very rare that all three strains in an influenza vaccine change in a single year. Therefore, you will see repeating strains if you watch the vaccines’ contents.

    People need a yearly influenza vaccine for two reasons: the vaccines usually contain new strains each year, and immunity to influenza decreases over time. The yearly vaccine helps keep your immunity strong and ensures that you have resistance to the strains scientists have identified as important for the year.

  • Question

    My 4 year-old son recently had anaphylaxis after the following vaccinations were given at the same time: chickenpox, DTP, polio, and MMR. Immediately after these immunizations in our pediatrician's office, he complained of his throat hurting, was sneezing, drooling, threw up and had red, itchy skin and trouble breathing. He was taken by ambulance to the ER, and treated with shots including epinephrine. In the past, he has had drooling and vomiting after eating a piece of protein chocolate bar and when taking his gummy vitamins, and complained of his throat hurting after eating marshmallows. My son doesn't have any hay fever, and we don't have a family history of allergies. Do you have any idea what could be causing these reactions?

    Answer

    Based on the information you’ve provided, your child’s reactions may be related to gelatin, which is added as a stabilizer to some vaccines and is found in both the MMR (measles-mumps-rubella) and chickenpox (varicella) vaccines. Yellow fever vaccine and rabies vaccine also contain gelatin, but are not part of the routine childhood vaccination schedule. 

    The foods you list also frequently contain gelatin.

    Neomycin, an antibiotic, is another ingredient in some vaccines which can be related to allergic reactions; it can also result in a reaction if used with topical application (as in “triple antibiotic” antibacterial skin creams, sold over-the-counter). 

    Your allergist can evaluate the possibility of a gelatin (or other) allergy and perform testing on your child to confirm. Given the circumstances, any further vaccinations should be held – and foods containing gelatin avoided – until the exact cause of reactions has been determined.

  • Question

    I am a 66 year-old man who was recently discharged from the hospital after a prolonged and resistant bout of pneumonia. After seeing an allergy/immunology doctor for an evaluation of a possible immune deficiency problem, I had some lab studies done. A certain test called gamma globulin came back in the low normal range, but some of the other tests were not quite normal. The allergist recommended that I have a Pneumovax (pneumococcal vaccine) and a tetanus/diptheria/pertussis vaccination and then have some repeat blood tests. Is it really necessary to have both of these vaccines? How do they help to identify if I have an immune problem?

    Answer

    Someone with an immune deficiency is very likely to have low normal or even normal gamma globulin levels but still have an inability to make antibodies to specific organisms such as pneumococcus (a bacteria which can cause pneumonia).

    The blood work you had taken likely showed your allergist that you lacked proper antibodies to specifically fight pneumococcal diseases and that you lacked protection against tetanus and/or diphtheria. The absence of these antibodies does not in itself mean that you have an immune problem. You may have lost the immunity from the diphtheria/tetanus/pertussis that you had as a child, and may simply not have been exposed to many of the pneumococcal organisms that were tested in the blood.

    However, you do need protection against all these organisms – that’s a standard recommendation for all adults over 65! Receiving the vaccines your physician has recommended will likely give you that protection. Repeating the blood tests 4 weeks afer the vaccinations will help your allergist know if your immune system is functioning properly. You really need both vaccinations for protection and to gain necessary information about your immune system. If your body shows an inadequate response to these vaccines, further immune studies and treatment, possibly long-term, may be required.

    These vaccines can be administered at the same time. I would suggest that you follow your allergist’s advice and obtain the vaccines and then the blood tests 4 weeks later.