The study team plans to enroll a total of 40 subjects with self-reported perimenstrual acne. Eligible women will be over the age of 18 and not on any current therapy. The patients will first arrive for a screening visit, where they will be given questionnaires on acne quality of life (acne QOL) and subjective assessments as well as flare ups (as used in the study by Geller et al). The patients' skin will be assessed for inflammatory and non-inflammatory acne vulgaris. The baseline visit (day 1) will be scheduled for one week prior to the first day of menses (as studies indicate that most women have their acne flare during this time). The study team will perform a zit count (counting papules, pustules, and comedones) and global assessment, and the patient will be instructed to record their menses (which they will do for the duration of the study). The patients will then return in 2 weeks, at day 15, and they will be re-assessed. The patients will be dispensed the investigational product and instructed on its daily use. The patients will continue to return every 14 days to have their skin assessed until their final visit on day 99, one week after their 3rd menses on treatment (4th menses on study). The duration of the study per patient is approximately 4 months, and the study team anticipates an enrollment period of 12 months.

Inclusion Criteria:

• Women 18 years or older
• Women who have had their first menses at least 12 months ago, and who currently have regular menses.
• Subjects must be able to read and understand English, and be able and willing to complete the survey.
• Subjects must have a self-reported complaint of peri-menstrual acne which has occurred monthly for the last 6 months.
• Subjects must be willing to forego any other therapy to the treatment area for the duration of the study.
• Subject is willing and able to participate in the study as an outpatient, making frequent visits to the study center during the treatment and follow-up periods and to comply with all study requirements including concomitant medication and other treatment restrictions.
• Subjects must have a negative urine pregnancy test result prior to study treatment initiation and must agree to use an approved method of birth control while enrolled in the study.
• Subjects must be willing to use a form of birth control during the study. For the purpose of this study, the following are considered acceptable methods of birth control: oral contraceptives, Norplant, Depo-Provera, double barrier methods (e.g., condom and spermicide) and abstinence.

Exclusion Criteria:

• Male subjects.
• Post-menopausal women.
• Women who do not suffer from acne.
• Subjects who are allergic to clindamycin, benzoyl peroxide, lidocaine or any other ingredients listed in the study medication.
• Subjects with an unstable medical condition as deemed by the clinical investigator.
• Subjects with ulcerative colitis or Crohn's disease.
• Subjects with any dermatologic disease in the treatment area that may be exacerbated by the treatment proposed or that might impair the evaluation of acne.
• Women who are pregnant, lactating, or planning to become pregnant during the study period.
• Subjects who have used any topical prescription medications on the study area within 30 days prior to Visit 2 / Baseline.
• Subjects on a stable dose of oral contraceptives for less than 6 months.

99 days