Goose bump like things on the arms are clinically classified into the following conditions: 1. Common perfollicular keratosis, mainly a genetic disorder, occurs mostly on the extensor side of the upper arm, with papules of follicular consistency, which can be treated with a regimen of fruit acids applied to the affected area, so that the blocked follicular pores are opened and the rash is relieved. Vitamin A acid ointment can also be applied, once a day and night, for the same reason of exfoliating excess keratin so that the follicular pores are opened. 2. Eczema due to allergies is often also symmetrically distributed, but the boundaries are not clear. In addition to small papules like goose bumps, there can be rashes such as erythema, papules and so on, and accompanied by a certain amount of itching. You can take oral Orotadine hydrochloride tablets, one in the morning and one in the evening, and apply topical Denide ointment. This disease is caused by allergies and often requires avoidance of a spicy, stimulating diet.