What does an allergy to flea bites look like? - briefly
Allergic reactions to flea bites usually manifest as sharply red, raised papules with pronounced itching, often grouped on the lower legs or ankles. Severe responses may include hives, blistering, or systemic symptoms such as fever.
What does an allergy to flea bites look like? - in detail
Allergic reactions to flea bites manifest as a distinct set of cutaneous and systemic signs. The skin response typically begins within minutes to a few hours after exposure and may progress over several days.
The primary dermatological features include:
- Red, raised papules or wheals centered on the bite site
- Intense itching that can lead to excoriation and secondary infection
- Swelling that may extend beyond the immediate bite area, especially on the lower extremities
- A “halo” of erythema surrounding the central lesion in severe cases
Systemic manifestations, though less common, can appear as:
- Generalized hives (urticaria) distributed across the body
- Facial or lip swelling (angio‑edema)
- Respiratory difficulty if airway involvement occurs
- Low‑grade fever and malaise during extensive reactions
The temporal pattern often follows a biphasic course: an early phase marked by immediate itching and redness, followed by a delayed phase characterized by larger, more inflamed plaques that may persist for several days. Chronic exposure can lead to sensitization, resulting in increasingly pronounced reactions with each subsequent bite.
Diagnostic confirmation relies on:
- Clinical history of flea exposure and characteristic lesion distribution
- Skin prick testing or intradermal testing with flea antigen extracts
- Blood tests showing elevated serum IgE specific to flea proteins
Management strategies focus on symptom control and prevention:
- Topical corticosteroids to reduce inflammation and itching
- Oral antihistamines for pruritus and urticaria
- Systemic corticosteroids for severe, widespread reactions
- Environmental measures such as regular pet grooming, vacuuming, and use of flea control products to eliminate the source
Monitoring for secondary bacterial infection is essential; prompt antibiotic therapy is indicated if signs of cellulitis develop.