Sweat hair in the skin can not grow out, most of them are due to pore blockage, that is, caused by peri-hair keratosis, the surface of the hair follicle has round small particles, slightly harder than normal skin, pick off the round small particles, you can see the curly hair accumulation in the pores, can not grow out of the body normally. In addition, there is another kind of sweat hair growth in other parts of the body, but not in the armpits, this situation is relatively rare, but belongs to the normal phenomenon. The above two cases can be treated without treatment if they do not affect the body, and will gradually improve with age. The cause of periorbital keratosis is unknown, but it has a certain genetic tendency and may be related to vitamin deficiency, metabolic disorders, endocrine disorders and other factors. Patients can apply Adapalene gel or compound lactic acid cream if needed under the guidance of a doctor, which can usually restore the normalization of the keratinized hair follicle opening in 5-10 days. But usually can not be cured, after stopping the drug for a period of time will again form keratinization, affecting the growth of sweat hair. In addition, patients should usually pay attention to personal hygiene, use warm water for skin washing and care, pay attention to diet and nutrition, can moderate consumption of food rich in vitamin A, can do local moisturizing, such as the application of maintenance products with moisturizing function, reduce skin dryness.