Tick Bite Reactions

Acute allergic reactions from the bites of the common dog tick, Dermacentor variabilis, resemble reactions from bites of mosquitoes and other insects. Following removal of the tick from the patient's back, this inflamed, pruritic plaque developed at the site (A). Once all parts of the tick are removed, these bites generally respond to topical corticosteroids.

Despite such therapy and complete removal of the tick, some bite reactions persist for months. A pruritic, granulomatous papule on another patient's back was still evident after 6 months (B). Intralesional corticosteroid injections may clear the site.

If this treatment fails, punch biopsy with complete removal of the papule may be necessary.