Oral N-acetylcysteine for Protection of Human Nevi Against UV-induced Oxidative Stress/Damage in Vivo

Inclusion Criteria:

Must have at least 2 nevi (each >6 mm diameter) not clinically suspicious for melanoma that can be biopsied.
Must be able to receive informed consent and sign an approved consent form that conforms to federal and institutional guidelines.

Exclusion Criteria:

The patient is a minor (< 18 years old).
The patient cannot speak/understand English or Spanish. (NOTE: A Spanish consent form and certified interpreter can be made available if needed)
The patient is pregnant. (NOTE: All female patients who have not had a hysterectomy and are not post-menopausal (i.e. post-menopausal for 1 year and not of child-bearing potential) will have a urine pregnancy test.)
The patient is a prisoner, critically or mentally ill, or otherwise incapacitated or considered vulnerable.
The patient has history of allergic reaction to NAC.
The patient has history of severe asthma.
The patient has been taking NAC or any other oral antioxidant.
The patient has recent history (i.e., 3 months) of sunless tanning (tanning bed) or extensive sunburn.