A study published in this month’s Medical Journal of Australia sheds light on the major causes of anaphylaxis and the findings may be counter-intuitive to some, especially during this time of increasing rates of food allergy.
The authors write that on November 1, 2018, the Victorian Department of Health and Human Services began accepting anaphylaxis as a notifiable condition. The ruling allowed the incidence, causes, and characteristics of anaphylaxis to be studied for the first time.
The researchers analyzed all cases of anaphylaxis during a 26-month span running from November 1, 2018 through December 31, 2020.
As reported in the study:
A total of 4273 anaphylaxis episodes were reported (females: 2292 cases, 54%); the overall anaphylaxis rate was 31.9 episodes per 100,000 person-years. The most frequently reported causes were foods (2659 cases, 62%); drugs were implicated in 533 cases (12%), insect venoms in 342 (8%), and other causes in 144 (4%). No deaths were recorded. The median age in cases of food-related anaphylaxis was 17 years; and 45 years in cases of drug-related anaphylaxis.
Hospitalisation was required by 1538 patients (36%) and intensive care by 111 (2.6%; 7% of people admitted to hospital).
Antimicrobial drugs were implicated in 258 cases of drug-related anaphylaxis (48%) and non-steroidal anti-inflammatory drugs in 85 cases (16%). Penicillin-class agents were implicated in 143 cases of antimicrobial-related anaphylaxis (56%), cephalosporins in 80 cases (31%).
To put this into perspective, 1 of every 8 cases of anaphylaxis was triggered by drugs and of those, roughly half were triggered by antimicrobials. Anti-microbials include penicillin and cephalosporins, drugs that are commonly prescribed for a wide range of infections.
Non-steroidal anti-inflammatory drugs (NSAIDs) were implicated in roughly 1 in 6 cases of anaphylaxis that were triggered by drugs. NSAIDs include common, over-the-counter pain relievers like aspirin, ibuprofen (Motrin, Advil), and naproxen (Aleve).
One takeaway from this study for individuals coping with food allergies is that a reaction can be caused by factors outside of your usual food triggers and to be especially vigilant during those times you are taking medications.
That said, the course of action when you suspect anaphylaxis triggered by food, a drug, or insect venom is the same: immediately administer epinephrine and call 911.
NEVER be caught without your life preserver: remember to take two epinephrine auto-injectors along everywhere, every time.