Allergies have a lot of small red spots may be caused by drug dermatitis, contact dermatitis, urticaria, etc., the treatment of different diseases. 1. Drug dermatitis: is the drug through oral, injection, inhalation and other ways into the body after the skin, mucous membrane inflammatory reaction, manifested as erythema, maculopapular rash, etc., in severe cases can be involved in other systems. It is necessary to stop the use of sensitizing drugs immediately, take antihistamines such as loratadine tablets, oral glucocorticoids are needed in severe cases, according to the skin lesions with topical glucocorticoids and other drugs. 2. Contact dermatitis: It is an inflammatory reaction of the skin after contact with certain sensitizers, which can be manifested as more erythema and papules at the contact site and distant sites. We should find the cause of the disease, quickly get rid of the sensitizer, according to the condition of oral antihistamine drugs such as loratadine or glucocorticosteroids. 3. Eczema: It is an allergic reaction triggered by contact with allergens or environmental changes. Allergens should be removed, and different topical medications should be chosen according to the lesions of acute, subacute and chronic eczema, and antihistamines such as loratadine can be taken orally. No matter which of the above causes of allergy, allergens should be quickly removed, different skin lesions choose different types and dosage forms of topical drugs, should go to the dermatology department, under the guidance of the doctor symptomatic treatment. In case of respiratory distress, laryngeal edema, diarrhea, etc., please go to the emergency room immediately.