Small blisters on the lips, to consider is caused by a variety of conditions: 1, consider the possibility of herpes simplex, herpes simplex is mainly due to the herpes simplex virus infection caused by common triggering factors, including being in a high-temperature environment, low immunity, as well as certain skin diseases lead to impaired skin barrier function, usually can be used topical antiviral drugs, common such as acyclovir cream, penciclovir Topical antiviral medications, such as acyclovir cream and penciclovir cream, are commonly used. If the disease is serious, you can take oral antiviral drugs, common such as valacyclovir hydrochloride dispersible tablets. 2, but also consider the possibility of lipitis, the cause of which is not known, may be related to certain cosmetics or pharmaceutical stimulation, spicy food, as well as sun exposure, climate change, neuropsychiatric factors, usually can choose to use topical calcium-modulated phosphatase inhibitors, common such as tacrolimus ointment.