What is the role of hydrocortisone injection in the treatment of anaphylactic shock?

Hydrocortisone in Anaphylactic Shock: Secondary Adjunct Only

Hydrocortisone 200 mg IV is a secondary adjunctive therapy in anaphylactic shock that should only be administered AFTER epinephrine and initial stabilization—it has no role in acute symptom reversal and should never delay or replace epinephrine administration. 1

Primary Treatment Algorithm

Epinephrine is the only first-line treatment for anaphylactic shock and must be given immediately: 1, 2

• Intramuscular route preferred initially: 0.3-0.5 mg (0.5 mL of 1:1000 solution) into the anterolateral thigh for adults 1
• IV epinephrine for shock: 0.05-0.1 mg IV bolus (5-10% of cardiac arrest dose) when IV access already established, or continuous infusion at 5-15 μg/min for refractory hypotension 1
• Aggressive fluid resuscitation: Large volumes of normal saline or lactated Ringer's solution via large-bore IV 1

Why Hydrocortisone Has Limited Acute Value

The mechanism of glucocorticoids explains their ineffectiveness in acute anaphylaxis: 1, 2

• Onset of action is 4-6 hours minimum because they work by binding to glucocorticoid receptors, translocating to the nucleus, and inhibiting gene expression—this cannot reverse acute cardiovascular collapse or bronchospasm 1, 2
• No evidence for preventing biphasic reactions: Despite widespread use, glucocorticoids are not reliable interventions to prevent biphasic anaphylaxis 2
• Lack critical pharmacologic effects: Unlike epinephrine, they have no vasoconstrictive, bronchodilatory, ionotropic, or immediate mast cell stabilization properties 1

When to Consider Hydrocortisone

Administer hydrocortisone 200 mg IV only as secondary management after epinephrine and stabilization in these specific scenarios: 1, 2

• Patients with underlying asthma or those recently treated with corticosteroids 1
• Severe or prolonged anaphylaxis requiring multiple epinephrine doses 2
• History of idiopathic anaphylaxis 2
• After initial resuscitation is underway—never delay epinephrine to give hydrocortisone 1

Alternative dosing: Oral prednisone 0.5 mg/kg may be sufficient for milder reactions 1

Critical Pitfalls to Avoid

Never use hydrocortisone as first-line therapy or in place of epinephrine—this dangerous practice contributes to anaphylaxis fatalities: 2, 3, 4

• Delay in epinephrine administration is directly associated with increased mortality and biphasic reactions 2, 3
• Glucocorticoids cannot address acute cardiovascular collapse or respiratory distress 1, 2
• Even mild initial symptoms can rapidly progress to fatal reactions, making immediate epinephrine critical regardless of apparent severity 3

Complete Secondary Management Protocol

After epinephrine and fluid resuscitation, consider these adjuncts in order: 1

1. Chlorphenamine (H1 antihistamine): 10 mg IV for adults—addresses only cutaneous symptoms (urticaria, itching) with slow onset 1
2. Hydrocortisone: 200 mg IV for adults 1
3. Alternative vasopressors: If hypotension persists despite epinephrine infusion, consider metaraminol or other vasopressors 1
4. Bronchodilators: IV salbutamol infusion or inhaled beta-2 agonists for persistent bronchospasm refractory to epinephrine 1

Monitoring Requirements

Patients in anaphylactic shock require: 1

• Close cardiovascular and respiratory monitoring as status can change rapidly 1
• Mast cell tryptase levels at initial presentation, 1-2 hours, and 24 hours for diagnostic confirmation 1
• Transfer to critical care area for severe cases 1