Why do bedbug bites not heal? - briefly
Bedbug bites persist because the insects deliver anticoagulant and anesthetic compounds that trigger a prolonged inflammatory reaction, and the tiny puncture sites are prone to secondary infection. The resulting immune hypersensitivity and possible bacterial colonization delay wound closure and maintain itching.
Why do bedbug bites not heal? - in detail
Bedbug saliva contains anticoagulants, vasodilators, and anesthetic proteins that prevent blood clotting and mask pain while the insect feeds. These substances remain in the skin after the bite, provoking a prolonged inflammatory response. The immune system recognizes the foreign proteins and releases histamine, cytokines, and leukocytes, which cause redness, swelling, and itching that can last for several days or weeks.
Repeated exposure to the same antigens can lead to sensitization. In sensitized individuals, mast cells degranulate more aggressively, producing larger wheals and extended pruritus. Persistent scratching damages the epidermis, creating micro‑abrasions that delay re‑epithelialization and increase the risk of secondary bacterial infection. Infection introduces additional inflammatory mediators, further prolonging wound healing.
Factors that impede resolution include:
- Age and immune status – older adults or immunocompromised patients exhibit slower cellular turnover and reduced inflammatory regulation.
- Skin conditions – eczema or psoriasis compromise barrier function, making lesions more resistant to closure.
- Allergic predisposition – atopic individuals mount stronger IgE‑mediated reactions, extending edema and erythema.
- Secondary infection – Staphylococcus aureus or Streptococcus pyogenes colonization adds pus formation and tissue necrosis, requiring antimicrobial therapy for recovery.
Effective management targets each component. Antihistamines reduce histamine‑driven itching; topical corticosteroids suppress cytokine production and edema; antibiotics treat confirmed bacterial superinfection; and wound care—gentle cleansing, moisture‑balanced dressings, and avoidance of excessive scratching—supports re‑epithelialization. When all contributing factors are addressed, lesions typically resolve within two to three weeks; otherwise, chronic nodules may persist for months.