Thigh itching and scratching into pieces of red bumps are mostly seen in hives, insect bite dermatitis, eczema, etc., according to the cause of the choice of application of drugs and oral medication. 1. Hives: mostly triggered by contact with allergens or eating allergenic foods, localized wind bumps of varying sizes will appear, resulting in itchy thighs and scratching pieces of red bumps. You can take loratadine tablets, cetirizine hydrochloride tablets and other drugs, can play the role of anti-allergy, anti-itch. 2. Insect bite dermatitis: mosquito bites may also trigger severe itching, scratching with the hands will also lead to thigh itching and scratching into pieces of red bumps. Can be applied locally glycerine lotion, hydrocortisone butyrate cream and other drugs, can play the effect of itching, usually after a period of time will be able to return to normal. 3. Eczema: prolonged mental stress or in a humid environment, will induce the skin to appear excessive immune response caused by eczema, resulting in severe itching of the skin, thigh itching and scratching into pieces of red bumps and other symptoms. Anti-inflammatory and anti-itch medications such as mometasone furoate cream and tretinoin acetate cream can be applied to control the development of the condition. There may be other reasons for itchy thighs and red bumps, so it is recommended to go to the hospital in time to clarify the cause of the disease and follow the doctor’s instructions for treatment.