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Food Allergy Treatments

Medication continued...


Drug Category: Adrenergic agonists


Used in the emergency management of systemic allergic reactions or anaphylaxis (eg, urticaria, angioedema, bronchospasm, cardiovascular collapse). Effects are immediate and dramatic. Appropriate use of this class of medication can be lifesaving, especially in the emergency management of anaphylaxis.

Drug NameEpinephrine (Adrenaline, EpiPen)
DescriptionDOC for treating anaphylaxis. Helps decrease symptoms of anaphylaxis by increasing systemic vascular resistance, elevating diastolic pressure, producing bronchodilation, and increasing inotropic and chronotropic cardiac activity. In addition, helps reduce urticaria, angioedema, laryngeal edema, and other systemic manifestations of anaphylaxis.
Adult Dose0.3 mL SC of 1:1000 aqueous injected (usual range is 0.2-0.5 mL) q10-15min, not to exceed 3 doses; may need to decrease dose to 0.2 mL in elderly persons or those with known cardiac conditions
0.3 mL IM of 1:1000 dilution q10-15min; IV route (1:10,000) seldom used; not to exceed 0.25 mg; given very slowly and with extreme caution
0.3-mg self-injectable devices (Epi-Pen)
Pediatric DoseIM dosing in children based on weight or 0.01 mL/kg IM of 1:1000 dilution; not to exceed 0.3 mL IM
1:2000 dilution q10-15min0.15-mg self-injectable devices (Epi-Pen Jr)
ContraindicationsDocumented hypersensitivity; cardiac arrhythmias, coronary artery insufficiency, or angle-closure glaucoma; local anesthesia in areas such as fingers or toes because vasoconstriction may produce sloughing of tissue; do not use during labor (may delay second stage of labor)
InteractionsIncreases toxicity of beta- and alpha-blocking agents and that of halogenated inhalational anesthetics, ie, drugs that may sensitize the heart to arrhythmias
PregnancyC - Safety for use during pregnancy has not been established.
PrecautionsDose may be decreased in elderly patients to 0.2 mL; may cause disturbing reactions such as fear, anxiety, tenseness, restlessness, throbbing headache, weakness, dizziness, pallor, respiratory difficulty, palpitation, tachycardia, tremor, and arrhythmia; use with caution in patients with cardiovascular disease, hyperthyroidism, and diabetes; properly train patients with use of self-injectable devices; advise patients to seek medical attention if using self-injectable devices to manage allergic reactions



Drug Category: Antihistamines (histamine-1 blockers)


Inhibit many responses to histamine. Histamine, via H1 receptors, causes smooth muscle contraction, increased capillary permeability, and formation of edema. During hypersensitivity reactions, histamine is one of the major potent mediators released. Blocking effects of this mediator with specific antihistamines is useful in emergency management of allergy symptoms.


Drug NameDiphenhydramine (Benadryl, Benylin)
DescriptionFrequently used antihistamine for management of acute allergic symptoms. Medication has significant antimuscarinic activity and pronounced tendency to induce sedation. Approximately half of those treated with conventional doses experience some degree of somnolence.
Adult Dose25-50 mg PO q6h
50-75 mg IV/IM q6h; IV drip may afford better control of symptoms (5 mg/kg/d); not to exceed 300 mg in 24 h
Pediatric Dose1-2 mg/kg/dose PO q6h
1-2 mg/kg/dose IV/IM q6h; IV drip may afford better control of symptoms (5 mg/kg/d)
ContraindicationsDocumented hypersensitivity; MAO inhibitors; glaucoma, gastrointestinal obstruction, hyperthyroidism, hypertension, and cardiovascular disease; may limit use in elderly patients
InteractionsPotentiates effect of CNS depressants; due to alcohol content, do not give syrup dosage form to patient taking medications that can cause disulfiramlike reactions
PregnancyB - Usually safe but benefits must outweigh the risks.
PrecautionsAdverse anticholinergic effects and drowsiness; large doses may depress respiration; use can potentially worsen glaucoma, gastrointestinal or urinary obstruction, hyperthyroidism, and hypertension; dizziness, paradoxical excitement, gastritis, and blood dyscrasias; caution with performing certain motor skills (eg, operating heavy machinery, driving a motor vehicle)

WebMD Medical Reference from eMedicineHealth

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