In all patients, always inquire about any allergy and clearly document it in the chart. Re-evaluate this periodically.
Clarify the manifestations of a reaction in order to try to diagnose a true allergic reaction (e.g., do not misdiagnose viral rashes as antibiotic allergy, or medication intolerance as true allergy).
In a patient reporting allergy (e.g., to food, to medications, environmental), ensure that the patient has the appropriate medication to control symptoms (e.g., antihistamines, bronchodilators, steroids, an EpiPen).
Prescribe an EpiPen to every patient who has a history of, or is at risk for, anaphylaxis.
Educate appropriate patients with allergy (e.g., to food, medications, insect stings) and their families about the symptoms of anaphylaxis and the self-administration of the EpiPen, and advise them to return for immediate reassessment and treatment if those symptoms develop or if the EpiPen has been used.
Advise patients with any known drug allergy or previous major allergic reaction to get a MedicAlert bracelet.
In a patient presenting with an anaphylactic reaction:
Recognize the symptoms and signs.
Treat immediately and aggressively.
Prevent a delayed hypersensitivity reaction through observation and adequate treatment (e.g., with steroids).
In patients with anaphylaxis of unclear etiology refer to an allergist for clarification of the cause.
In the particular case of a child with an anaphylactic reaction to food:
Prescribe an EpiPen for the house, car, school, and daycare.
Advise the family to educate the child, teachers, and caretakers about signs and symptoms of anaphylaxis, and about when and how to use the EpiPen.
In a patient with unexplained recurrent respiratory symptoms, include allergy (e.g., sick building syndrome, seasonal allergy) in the differential diagnosis.
Drug Reaction Classification
Type A - Adverse reaction
Type B - Hypersensitivity
Exaggerated sensitivity to known drug toxicity (eg. tinnitus with single dose of aspirin)
Idiosyncratic drug reaction (due to genetic differences, eg. hemolytic anemia in G6PD after primaquine)
Immunologic/Drug allergy
Type I - Immediate IgE (mast cells +/- basophils)
Within 30mins-1h
Urticarial rash, pruritus, flushing, angioedema, wheezing, GI symptoms, hypotension
Anaphylaxis is most severe type of presentation
Type II - Delayed antibody (IgG) mediated cell destruction
Usually 5-8d after exposure
Hemolytic anemia, thrombocytopenia, neutropenia
Type III - Delayed IgG:drug immune complex deposition and complex activation
Acute onset of illnesss (minutes to several hours) with involvement of skin, mucosal tissue or both (eg, generalized hives, pruritus or flushing, or swollen lips-tongue-uvula) and at least one of the following:
Respiratory compromise (eg, dyspnea, wheeze-bronchospasm, stridor, reduced PEF or hypoxemia)
Reduced BP or associated symptoms of end-organ dysfunction (eg, hypotonia [collapse], syncope or incontinence)
Two or more of the following that occur rapidly after exposure to a likely allergen for that patient (minutes to several hours):
Involvement of the skin-mucosal tissue (eg, generalized hives, itch-flush or swollen lips-tongue-uvula)
Respiratory compromise (eg, dyspnea, wheeze-bronchospasm, stridor, reduced PEF or hypoxemia)
Reduced BP or associated symptoms of end-organ dysfunction (eg, hypotonia [collapse], syncope or incontinence)
Persistent gastrointestinal symptoms (eg, crampy abdominal pain or vomiting)
Reduced BP after exposure to a known allergen for that patient (minutes to hours)
Low BP for children defined as <70mmHg + [2 x age] up to 10yo