A bag at the mouth of the nose that hurts when you touch it may be caused by folliculitis, acne, nasal vestibular cysts with infections, and so on. 1. Folliculitis: due to the stasis of the hair follicles caused by the infection of the nasal mucosa by pathogens such as Staphylococcus aureus, the situation of pain when touched is accompanied by itching. 2. Acne: a common chronic inflammatory disease of the sebaceous glands of the hair follicles, when the microscopic pores are blocked, it will cause the appearance of acne, which is usually characterized by pustules, nodules and cysts, accompanied by sebum overflow, which will cause pain when touched. 3. Nasal vestibular cyst with infection: it is a kind of cyst that develops under the mucous membrane of the nasal vestibule, and when it is limited to acute suppurative infection, it will lead to the appearance of a bag at the mouth of the nose that hurts when touched. If the symptoms do not subside, it is recommended that the patient go to the hospital in a timely manner, after a clear diagnosis by the doctor, according to the patient’s specific condition, to take targeted treatment.