What should you know about rash after bug bite?

A small raised bump, itch, and limited redness can follow bites from mosquitoes or other insects. Several bumps in a line or cluster may reflect repeated bites. A rash that spreads beyond the bite, forms hives, or affects the face can be an allergic response. Increasing warmth, tenderness, pus, or fever suggests possible infection rather than a simple bite reaction.

Other rashes can appear at the same time by coincidence. A clinician may consider [Scabies](/conditions/scabies/), [Ringworm](/conditions/ringworm/), [Contact Dermatitis](/conditions/contact-dermatitis/), or other causes when the pattern does not settle.

Wash the area with soap and water, apply a cool cloth, and keep fingernails short. Avoid squeezing the bump or using strong household chemicals. A pharmacist can advise on an itch-relieving product that fits your age, pregnancy status, and other medicines.

Take a photograph and mark the edge of expanding redness so you can describe change accurately. Arrange a clinical review if symptoms keep worsening, the site becomes painful or infected-looking, or new lesions continue appearing after you have left the exposure.

Seek emergency help for breathing difficulty, throat tightness, swelling of the lips or tongue, faintness, or widespread hives. Seek prompt medical care for rapidly expanding redness, severe pain, fever, red streaks, pus, or a bite near the eye.

Ask whether the pattern fits a bite, allergy, or infection; whether treatment is needed; and how long to monitor it. Tell the clinician where you were, whether anyone else has a similar rash, and what creams or medicines you have already used.