How can I differentiate between a mild allergic reaction and anaphylaxis in a patient who has been stung by a bee?

To differentiate between a mild allergic reaction and anaphylaxis in a patient stung by a bee, assess the severity and systems involved:

• Mild allergic reaction typically involves localized symptoms such as erythema, pruritus, swelling, or a large local reaction (oedema and erythema >10 cm) that peaks 24–48 hours after the sting without systemic involvement.
• Anaphylaxis is a severe, life-threatening systemic hypersensitivity reaction characterized by rapidly developing problems involving the airway (e.g., pharyngeal or laryngeal oedema), breathing (e.g., bronchospasm with tachypnoea), and/or circulation (e.g., hypotension and/or tachycardia), often accompanied by skin and mucosal changes such as urticaria or angioedema.
• Signs of anaphylaxis include difficulty breathing, swelling of the mouth, throat or tongue, hypotension, tachycardia, and collapse or shock, which are not present in mild reactions.
• Local toxic reactions from venom cause burning pain but usually subside within hours and do not involve systemic symptoms.
• Any suspicion of systemic hypersensitivity or anaphylaxis requires urgent treatment and immediate referral to emergency care.

In summary, the presence of systemic symptoms affecting airway, breathing, or circulation distinguishes anaphylaxis from a mild allergic reaction localized to the sting site ¹,²,³.