Insect bite dermatitis

Insect bite dermatitis is an inflammatory skin reaction that occurs after contact with various types of insects – mosquitoes, fleas, bedbugs, ants, ticks and others. It manifests itself with redness, swelling, itching and sometimes blisters or painful papules. The reaction can be mild and temporary, but in sensitive people or with repeated bites, a stronger inflammatory response or secondary infection can develop.
Most common causes
- **Mosquitoes** – itchy red papules, most often on exposed parts of the body
- **Fleas** – small, multiple bites on the legs, ankles, or below the waist
- **Woodworms** – linear clustered bites (often during sleep)
- **Ticks** – attachment to the skin, often painless, but with a risk of infections (e.g. Lyme disease)
- **Ants, wasps, bees** – painful bites or stings with redness and swelling
Symptoms
- Redness, itching and swelling at the site of the bite
- Formation of papules, vesicles or sometimes pustules
- Soreness or burning (especially when stung)
- Possible scratching and subsequent bacterial infection
- In sensitive individuals – more extensive edema or urticarial reaction
When is attention needed?
- In case of multiple bites with a general reaction (fever, weakness)
- If pus, swelling, pain appear - possible bacterial superinfection
- In case of allergic reactions – swelling of the lips, eyelids, difficulty breathing
- When bitten by a tick – risk of Lyme disease (monitor for erythema migrans)

Treatment
**Local treatment:**
- Cold compresses to relieve swelling
- Topical corticosteroids – for severe itching and inflammation
- Antihistamine gels or creams
- Disinfection when combing to prevent infection

**Systemic therapy:**
- Antihistamines (cetirizine, loratadine, etc.) for generalized itching
- For bacterial inflammation – local or systemic antibiotics (at the discretion of the doctor)

Insect bite dermatitis is common and usually benign. Timely treatment and precautions prevent complications and provide rapid relief from symptoms.