The itchy and swollen bites of small black bugs are usually insect bite dermatitis, which can be treated by general treatment, medication and other ways. 1. General treatment: After being bitten by the little black bugs, you need to do a good job of preventive measures to avoid being bitten by the little black bugs again. You should also keep the affected skin clean and dry, avoiding water, and should not scratch. 2. medication: insect bites can be applied to the local mint glycerite lotion to treat, which can play the astringent, anti-inflammatory effect. Patients can also take antihistamines as prescribed by the doctor to stop itching, such as loratadine, cetirizine and so on. If the local skin inflammation reaction is more serious, you can also apply Denard cream, hydrocortisone butyrate cream and other drugs to treat. In severe cases, patients with insect bite dermatitis may also experience respiratory distress, shock and other emergencies, at which time it is recommended to call the emergency number in time to be transferred to the hospital for resuscitation treatment. After being bitten by small black bugs, it is recommended to go to a regular hospital for a clear diagnosis, and cooperate with the doctor for active treatment.