painful blisters (eventually becoming ulcers) will often presenting on the lips or nasal mucosa. Infected individuals should avoid contact with others due to potential for transfer of the infection. Herpes labialis tends to be recurrent and often exacerbated by stress, sunlight, fever or illness.
treatment includes the use of antiviral creams (acyclovir) and oral medications (acyclovir). Pre-treatment with oral acyclovir, in those prone to cold sores (prior to sun exposure, etc.) has been shown to decrease exacerbations.