If the erythema is caused by decreased immunity or infection, gammaglobulin is an adjunctive treatment. Gammaglobulin is a variety of antibodies extracted from human blood, and these antibodies have the effect of enhancing the body’s immunity and fighting infections. It has direct and effective therapeutic effect on the decline of body immunity caused by various infections and various immunity-deficient diseases. If the facial erythema is caused by an immune system disease (systemic lupus erythematosus) or is not cured for a long period of time, and the simple application of hormones, antibiotics and other medications are not effective, then the use of gammaglobulin can be considered as an adjunctive treatment. However, there are many causes of facial erythema, not all types are suitable for the use of gammaglobulin, such as allergy, may need to use anti-allergy drugs, such as oral loratadine and so on. It is recommended to go to the hospital in time to find out the cause of facial erythema and treat the symptoms. The medication should be used according to the doctor’s prescription.