Fingers suddenly swollen and particularly itchy consider contact dermatitis, insect bite dermatitis, frostbite and so on. 1. Contact dermatitis: contact dermatitis is an inflammatory skin disease triggered by skin contact with external substances, can cause erythema, edema, and accompanied by itchy symptoms, you can apply glucocorticoid drugs, such as hydrocortisone cream, dexamethasone cream, the symptoms are more serious can be taken orally loratadine, cetirizine to relieve itching. 2. Insect bite dermatitis: this is an allergic reaction to insect bites, common in summer, the symptoms are mild and do not require special treatment, can be self-healing symptoms can be coated with glycerine lotion, glucocorticoid drugs, such as dexamethasone cream, tretinoin cream. 3. Frostbite: If it is a cold winter, do not pay attention to warmth, may be frostbite, which is caused by the cold, limited, bruised, inflammatory damage to the skin, mainly manifested as redness, swelling and itching, generally pay attention to warmth after the symptoms can be relieved, if the lesions are not broken, you can also apply vitamin E ointment and frostbite ointment. Fingers suddenly swollen and particularly itchy, according to the specific cause of the selection of appropriate treatment, the above medication should be used under the guidance of a doctor, avoid self-medication.