What is the treatment for a patient with itchy mouth, wearing (likely referring to urticaria or hives) on the chest, nausea, shortness of breath, and coughing, with a history of hypothyroidism and moderate persistent asthma?

Anaphylaxis Management

This patient is experiencing anaphylaxis and requires immediate intramuscular epinephrine, followed by supportive care with oxygen, bronchodilators, and systemic corticosteroids.

Clinical Recognition

This presentation of itchy mouth (oral pruritus), hives on the chest (urticaria), nausea, shortness of breath, and coughing represents a multi-system allergic reaction consistent with anaphylaxis. The combination of cutaneous symptoms (itchy mouth, urticaria) with respiratory symptoms (shortness of breath, coughing) and gastrointestinal symptoms (nausea) meets criteria for anaphylaxis requiring immediate treatment.

• The presence of respiratory symptoms alongside cutaneous manifestations indicates progression beyond simple urticaria and demands urgent intervention 1
• Patients with underlying asthma, particularly moderate persistent asthma as in this case, are at higher risk for severe respiratory compromise during anaphylactic reactions 1

Immediate Treatment Protocol

First-Line: Epinephrine

• Administer intramuscular epinephrine immediately as the primary treatment for anaphylaxis 1
• All patients with signs of anaphylaxis should receive epinephrine without delay, as this is the only medication proven to prevent progression to life-threatening complications 1

Second-Line: Respiratory Support

• Oxygen 40-60% should be administered immediately to address hypoxemia from bronchospasm and potential airway compromise 1
• Nebulized salbutamol 5 mg or terbutaline 10 mg via oxygen-driven nebulizer to treat bronchospasm, particularly critical given the patient's underlying moderate persistent asthma 1, 2

Third-Line: Systemic Corticosteroids

• Prednisolone 30-60 mg orally OR intravenous hydrocortisone 200 mg to prevent biphasic reactions and reduce inflammation 1, 2
• Corticosteroids should be administered early but do not replace epinephrine as first-line treatment 1, 2

Assessment of Severity

Monitor for features of severe or life-threatening reaction:

• Inability to complete sentences in one breath 1, 2
• Pulse >110 beats/min 1, 2
• Respirations >25 breaths/min 1, 2
• Silent chest, cyanosis, or feeble respiratory effort 2
• Hypotension, confusion, or altered consciousness 2

Observation Period

• Observe for at least 2 hours after symptom resolution for patients with minimal residual symptoms 1
• Extend observation to 4 hours if residual symptoms persist (such as new hives or lip swelling) 1
• Consider longer observation periods given the patient's history of moderate persistent asthma, as biphasic reactions can occur up to 6 hours after initial presentation 1

Critical Pitfall: The Hypothyroidism Connection

The patient's history of hypothyroidism is clinically relevant but does not change acute management. While autoimmune thyroid disease is associated with chronic urticaria in 4-43% of cases 3, 4, 5, 6, this association:

• Does not indicate that hypothyroidism is causing the current acute anaphylactic reaction 3
• L-thyroxine treatment has no effect on the course of chronic urticaria even when thyroid autoimmunity is present 3
• The acute presentation described here represents anaphylaxis requiring immediate treatment, not chronic urticaria exacerbation 1

Discharge Planning

After stabilization and appropriate observation:

• Prescribe self-injectable epinephrine (e.g., EpiPen) and ensure the patient demonstrates proper technique 1
• Provide written emergency action plan with clear instructions on recognizing anaphylaxis symptoms and when to use epinephrine 1
• Prescribe long-acting oral antihistamine for potential recurrent urticaria over the next 1-2 days 1
• Arrange allergy/immunology referral for identification of the triggering allergen and consideration of allergen immunotherapy if appropriate 1
• Continue usual asthma controller medications and ensure adequate supply with proper inhaler technique verification 2

Follow-Up Considerations

• Review within 24-48 hours to assess for delayed reactions and ensure proper use of emergency medications 2
• Complete thyroid evaluation if not recently performed, including TSH, free T4, and antithyroid antibodies (antithyroglobulin and antithyroperoxidase), as thyroid autoimmunity can develop years after chronic urticaria onset 4, 5
• Optimize asthma control with regular monitoring of symptoms and peak expiratory flow, as uncontrolled asthma increases risk during future allergic reactions 2