What is the cocktail of medicine to order for anaphylactic reactions?

From the Guidelines

For allergic reactions, the recommended medication cocktail typically includes an antihistamine like diphenhydramine (Benadryl) 25-50mg orally or intravenously, combined with a corticosteroid such as prednisone 40-60mg orally or methylprednisolone 125mg intravenously. For severe reactions (anaphylaxis), epinephrine (0.3-0.5mg intramuscularly via auto-injector or 1:1000 solution) is the first-line treatment and should be administered immediately 1. H2 blockers like famotidine (20mg) can be added to enhance the antihistamine effect. For respiratory symptoms, albuterol via nebulizer may help with bronchospasm. The antihistamine helps block histamine receptors to reduce itching, swelling, and hives; corticosteroids reduce inflammation but take hours to work; epinephrine rapidly constricts blood vessels, relaxes airways, and suppresses the immune response in severe reactions. Patients should be monitored for at least 4-6 hours after treatment as biphasic reactions can occur, and those with severe reactions should seek emergency care immediately even after using epinephrine 1.

Some key points to consider:

• Epinephrine is the drug of choice for anaphylaxis and should be administered as first-line therapy 1
• The dose of epinephrine is 0.01 mg/kg, up to 0.3 mg in children, and 0.3 to 0.5 mg in adults, depending on the severity of the reaction 1
• Antihistamines and corticosteroids should not be considered to be substitutes for epinephrine 1
• Patients with a history of prior anaphylactoid reactions to radiographic contrast material are at increased risk for anaphylactoid reactions 1
• Pretreatment regimens for prevention of repeat anaphylactoid reactions have consisted of oral glucocorticosteroids, H1 and H2 antihistamines, and other medications 1

From the FDA Drug Label

Emergency treatment of allergic reactions (Type 1), including anaphylaxis The signs and symptoms associated with anaphylaxis include flushing, apprehension, syncope, tachycardia, thready or unobtainable pulse associated with hypotension, convulsions, vomiting, diarrhea and abdominal cramps, involuntary voiding, airway swelling, laryngospasm, bronchospasm, pruritus, urticaria or angioedema, swelling of the eyelids, lips, and tongue. For amelioration of allergic reactions to blood or plasma, in anaphylaxis as an adjunct to epinephrine and other standard measures after the acute symptoms have been controlled

The cocktail of medicine to order for allergic reactions is:

• Epinephrine (IM): 0.3 to 0.5 mg (0.3 to 0.5 mL) intramuscularly or subcutaneously into anterolateral aspect of the thigh every 5 to 10 minutes as necessary for adults and children 30 kg (66 lbs) or more 2
• Diphenhydramine (IV): as an adjunct to epinephrine and other standard measures after the acute symptoms have been controlled 3

From the Research

Medications for Allergic Reactions

The primary medication for allergic reactions, particularly anaphylaxis, is epinephrine 4, 5, 6. It is administered intramuscularly and acts rapidly to reverse symptoms of anaphylaxis.

First-Line Treatment

• Epinephrine is the first-line treatment for anaphylaxis and should be administered promptly once anaphylaxis is suspected 4, 5, 6.
• It is essential for patients at risk of anaphylaxis to carry two epinephrine autoinjectors and know how to use them 4.

Adjunct Medications

• After epinephrine administration, adjunct medications such as histamine H1 and H2 antagonists, corticosteroids, beta2 agonists, and glucagon may be considered 5.
• Antihistamines may have a beneficial effect in anaphylaxis management, according to data from the Cross-Canada Anaphylaxis REgistry 7.
• The use of corticosteroids in anaphylaxis should be revisited, as they may be associated with increased need for intravenous fluids and hospital admission 7.

Management of Anaphylaxis

• Removal of the trigger, early administration of intramuscular epinephrine, and supportive care for the patient's airway, breathing, and circulation are crucial in managing anaphylaxis 5.
• Patients should be monitored for a biphasic reaction, which can occur within four to 12 hours after the initial reaction 5.
• Developing an emergency action plan, referral to an allergist, and patient education on avoidance of triggers and appropriate use of an epinephrine auto-injector are essential after an anaphylactic reaction 5.