URTICARIA - release of mediators from mast cells; increased vascular permeability. edmeatous wheals that are fleeting in nature and disappear within hours and return to another lcoation. Blanch with pressure and cause pruritis or stinging. Antihistamines are effective for symptomatic relief and steroids if severe
ANGIOEDEMA - similar to urticaria but involve deeper areas f the skin, no superficial. cn be caused by any precipitants of urticaris, ACE i are a specific acuse of angioedema that occurs within 1 week of administration. It can usually affect only the eyelids, lips, tongue, genitals, hands feet - urticaria can be anywhere. If severe this can lead to life threatening airway obstruction. Can invove the FI trat leading to n/v. Treatment is similar to urticaria. If severe then administere SN epi for laryngeal edema or bronchospasm.
Drug allergy: most drug reactions are not related to allergy. DI HS reactions can affect multple systems: dermatologica is the most common, pulmonary dinging (asthma, pneumonitis), renal manifestations )AIN, NEPHROTIC), or hematological manifestations, thrombocytopenia, HA, eos, agranulocytosis (PTU)). If suspected then ask about recent changes in pt meds. Allergy rxn appears within 1 mon of drug. NOT < than one week - r/o drug allergy if this is the case.
FOOD: HS are usualyl Ig (type II) - or IgE mediated. Most common response is to eggs, peanutm milk soy tree nuts shell fish wheat chochlate and legumes. Dematologica manifestiatoin are the most common (itchy redness, urticaria, andiogedema); GI manidestations n/v/d. anaphylactive reactions - respitatory system can be fatal; cutanous manifestaions.