Anaphylaxis, a potentially deadly allergic reaction that is rapid in onset, is most often caused or triggered by foods, medications and insect stings, but there can be many other possible triggers, such as medications as well. And though it is not frequently fatal, for some of it can be a matter of life and death.
“Anaphylactic reactions are unpredictable,” says Dr. Jennifer Rumpel, an allergist/immunologist on staff at St. Mary Medical Center in Hobart. “Many people who experience it have a known allergy. Some patients have had one or more allergic reactions previously. Others, who are not even aware that they have an allergy, can suddenly experience anaphylaxis. Even the first episode of anaphylaxis can be fatal.”
Anaphylaxis consists of sudden onset of mast cell degranulation into the body, which can cause hives, throat tightening, nausea, vomiting or diarrhea, says Rumpel, adding that a drop in blood pressure can also occur. Though the reactions and outcomes are not the same for everyone, other reactions can include swollen lips and tongues, plummeting oxygen levels, hypothermia and respiratory compromise resulting in difficulty breathing.
“The ABCs of anaphylaxis are airway, breathing and circulation," says Dr. Reuel Uy, a doctor of internal medicine in the Northwest Medical Group. “You go into shock when your blood pressure goes down and your blood vessels constrict, making it less efficient ... and cutting off the oxygen supply to the body.”
Uy says several things can cause anaphylactic shock.
“The first is food allergies and the second is medications,” he says. “Others are insect stings, be it bees, wasps or fire ants. And some are idiopathic, meaning they don’t know what caused it.”
The No. 1 indicator for those who are at risk of anaphylactic shock at those who have done so before, says Uy. Other risk factors include a history of asthma and allergies to foods or medicine.
“To prevent anaphylaxis, an allergist and immunologist can discuss with the family the best way to completely avoid an allergen. This requires ongoing education about the allergen and where it is likely to be encountered,” says Rumpel. “If you are aware that you are allergic to a trigger that may cause anaphylaxis, you should always carry an EpiPen.”
An EpiPen is a syringe and concealed needle to inject a single dose of epinephrine when pressed against the thigh. This stops the progression of the allergic response by constricting blood vessels and opening airways in the lungs. This raises blood pressure and reduces the swelling that are part of anaphylactic shock.
“When anaphylaxis occurs, if the diagnostic criteria is met, an EpiPen should be used and you should immediately proceed to the emergency department,” says Rumpel. “You can also take an antihistamine such as Benadryl, but this will not completely shut down the process of anaphylaxis. It is an adjunctive therapy in anaphylaxis.”
Uy says that if you’ve previously experienced anaphylaxis, your doctor can prescribe a EpiPen.
“If you’ve had a reaction before to certain foods, stay away from them,” he says. “This is harder but if you’ve had a reaction to bees or other stinging insects, try to avoid them. If you do need to use an EpiPen and don’t feel better, call a doctor. And if you’re in respiratory stress, go to the emergency room right away. You might need to be intubated if your distress is severe.”
In severe cases of anaphylaxis, hospitals can push fluids through the body to raise blood pressure and administer epinephrine with an IV. Steroids can also be administered to open airways in severe cases.
“It’s important to be proactive when preventing and treating anaphylaxis,” says Uy.