Estrostep (norethindrone acetate and ethinyl estradiol)

The following drug information is obtained from various newswires, published medical journal articles, and medical conference presentations.


Approval Status:

Approved July 2001

Specific Treatments:

Acne vulgaris

Therapeutic Areas

Find Related Trials for The Following Conditions

General Information

Estrostep (ethinyl estradiol and norethindrone acetate) is currently marketed for use as an oral contraceptive. In July 2001, the drug received FDA approval for a new indication: the treatment of moderate acne vulgaris (common acne) in females 15 years and older. The drug is designed for women who have no known contraindications to oral contraceptive therapy, and who desire oral contraception and have not responded to topical acne medications.

Over 20 million teenagers suffer from acne according to the American Academy of Dermatology. Furthermore, this common skin disease is not limited to adolescents and can affect men and women well into adulthood. The disease causes physical effects, which may range from moderate irritations to severe, painful lesions or boils, and imparts a psychological and social impact that can lead to poor self-image, embarrassment, anxiety and social isolation.

Clinical Results

Two randomized, double-blind, placebo-controlled, multicenter phase III trials evaluated Estrostep in the treatment of acne vulgaris. The mean age at enrollment for both groups was 24 years, and a total of 295 subjects received Estrostep while 296 received placebo. At six months, results showed a statistically significant difference between Estrostep and placebo in terms of mean change from baseline in lesion counts. Each trial also demonstrated overall treatment success in the investigator's global evaluation.

Side Effects

Most side effects of oral contraceptives are not serious. The following side effects have been reported with oral contraceptive use and are believed to be drug-related:

  • Nausea
  • Vomiting
  • Bleeding between menstrual periods
  • Weight gain
  • Breast tenderness
  • Difficulty wearing contact lenses
  • Migraine
  • Rash
  • Mental depression
  • Edema (fluid retention)

Although serious side effects occur infrequently, an increased risk of the following more severe conditions has been associated with the use of oral contraceptives:

  • Blood clots in the legs and lungs
  • Heart attack
  • Hypertension
  • Gallbladder disease
  • Liver tumors
  • Stroke

As with any medication, please consult a physician for a full list and explanation of possible adverse events.

Mechanism of Action

Acne is caused by several factors, including androgen stimulation and sebum production. The combination of norethindrone acetate and ethinyl estradiol increases sex hormone binding globulin (SHBG) and decreases free testosterone; however, the relationship between these changes and a decrease in facial acne in otherwise healthy women has not been established. (from Estrostep Labeling Information)

Additional Information

Please visit the product web site for additional information on Estrostep.

For more information on acne, please visit the American Academy of Dermatology or the Health Information section of the National Institute of Arthritis and Musculoskeletal and Skin Diseases.