One question I ask every new patient is “Are you allergic to anything?” I need to know. The goal is to avoid an allergic reaction, especially anaphylaxis. Anaphylaxis is a severe, life-threatening allergic reaction. Frequently it is not anticipated and may lead to death by airway obstruction or collapse of the body’s blood vessel system.
What are the most common triggers? Food. Insect stings. Medicines. Food-related allergic reactions are most common in children up to age four. Medication reactions are most common in patients older than 55.
- Common food triggers: egg, fish, food additives, milk, peanuts, sesame, shellfish, tree nuts.
- Insect venom: bee, wasp or fire ants.
- Medications: ACE inhibitor blood pressure medication, antibiotics like penicillin, aspirin, NSAIDs like ibuprofen, pain medications like opioids, radiocontrast media like iodine.
How common is it? In the US there are 50 cases per 100,000 person-years (or .05 to 2% lifetime chance). The risk is doubled in patients with mild asthma and tripled in those with severe asthma.
The diagnosis of anaphylaxis is made when symptoms occur within one hour of exposure to the trigger. It is a clinical diagnosis–meaning lab testing is not very helpful.
Common symptoms are
- swelling around the eyes, swelling of the tongue and lips,
- hives and itchy skin,
- wheezing or cough, sensation of throat constriction,
- fast heart rate, dizziness, vomiting,
- headache, anxiety, and feeling of impending doom.
Treatment is needed. Epinephrine is the mainstay, first-line treatment. Patients with known anaphylaxis should carry an Epi-Pen at all times. At the first symptom of anaphylaxis the patient should inject themselves in their muscle with epinephrine AND call 911! At the hospital additional medicines may be given: Histamines like benadryl, steroids, and oxygen.
Here is a video link for appropriate Epipen use. http://youtu.be/aUdvv55S8qQ