Red bumps on the chest and back and itchy, may be caused by eczema, urticaria, folliculitis and other diseases. 1. Eczema: the occurrence of eczema is related to a variety of internal and external factors, such as ultraviolet rays, pollen, food, animal fur, mental stress, genetic factors, etc., resulting in the appearance of skin erythema, pimples, pimples, etc. with obvious itching. 2. Urticaria: It is difficult to determine the cause of urticaria, such as changes in the living environment, intake of allergy-inducing food, resulting in erythema on the back of the chest and back, accompanied by itching. 3. Folliculitis: Folliculitis on the chest and back may be caused by bacterial infection or Malassezia infection, resulting in the appearance of single or multiple red papules locally, which may be accompanied by different degrees of itching. Red bumps on the chest and back with itching, it is recommended not to scratch the stimulus, to avoid inducing infection. You can go to the dermatology department of the hospital to look for the cause of the red bumps, and then use medication to treat the cause of the disease.