Following are six common causes of anaphylactic shock.
Penicillin
According to the World Allergy Organization (WAO), penicillin is the most common cause of anaphylaxis. Anaphylaxis occurs in “one to five per 10,000 cases of penicillin therapy.” That said, 90 percent of patients with a history of allergies to penicillin or similar medications are not truly allergic.
Penicillin allergy occurs when your immune system gets confused. In other words, it incorrectly assumes that penicillin is harmful -- like a virus. Consequently, your body may develop antibodies to the drug itself.
Fast forward to your next round of penicillin, and these antibodies give it an automatic red flag. That’s when chemicals are released, and an allergic reaction results.
Though symptoms often appear within an hour of taking this medication, they may appear many hours to weeks later. Symptoms of an allergic reaction can include skin rash, hives, itching, fever, swelling, shortness of breath, wheezing, runny nose, itchy/watery eyes and anaphylaxis.
Doctors can use a skin test to determine possible allergies to penicillin. If you are allergic, healthcare providers will discontinue treatment with penicillin and may prescribe antihistamines and corticosteroids. In the case of anaphylaxis, epinephrine will be administered.