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Included as part of the PRECAUTIONS section.

Ectopic Pregnancy

Ectopic pregnancies account for approximately 2% of all reported pregnancies. Up to 10% of pregnancies reported in clinical studies of routine use of progestin-only contraceptives are ectopic.

A history of ectopic pregnancy is not a contraindication to use of this emergency contraceptive method. Healthcare providers, however, should consider the possibility of an ectopic pregnancy in women who become pregnant or complain of lower abdominal pain after taking Plan B One-Step (levonorgestrel tablet) . A follow-up physical or pelvic examination is recommended if there is any doubt concerning the general health or pregnancy status of any woman after taking Plan B One-Step (levonorgestrel tablet) .

Existing Pregnancy

Plan B One-Step (levonorgestrel tablet) is not effective in terminating an existing pregnancy.

Effects on Menses

Some women may experience spotting a few days after taking Plan B One-Step (levonorgestrel tablet) . Menstrual bleeding patterns are often irregular among women using progestin-only oral contraceptives and women using levonorgestrel for postcoital and emergency contraception.

If there is a delay in the onset of expected menses beyond 1 week, consider the possibility of pregnancy.

STI/HIV

Plan B One-Step (levonorgestrel tablet) does not protect against HIV infection (AIDS) or other sexually transmitted infections (STIs).

Physical Examination and Follow-up

A physical examination is not required prior to prescribing Plan B One-Step (levonorgestrel tablet) . A follow-up physical or pelvic examination is recommended if there is any doubt concerning the general health or pregnancy status of any woman after taking Plan B One-Step (levonorgestrel tablet) .

Fertility Following Discontinuation

A rapid return of fertility is likely following treatment with Plan B One-Step (levonorgestrel tablet) for emergency contraception; therefore, routine contraception should be continued or initiated as soon as possible following use of Plan B One-Step (levonorgestrel tablet) to ensure ongoing prevention of pregnancy.

Patient Counseling Information

• Take Plan B One-Step (levonorgestrel tablet) as soon as possible and not more than 72 hours after unprotected intercourse or a known or suspected contraceptive failure.
• If you vomit within two hours of taking the tablet, immediately contact your healthcare provider to discuss whether to take another tablet.
• Seek medical attention if you experience severe lower abdominal pain 3 to 5 weeks after taking Plan B One-Step (levonorgestrel tablet) , in order to be evaluated for an ectopic pregnancy.
• After taking Plan B One-Step (levonorgestrel tablet) , consider the possibility of pregnancy if your period is delayed more than one week beyond the date you expected your period.
• Do not use Plan B One-Step (levonorgestrel tablet) as routine contraception.
• Plan B One-Step (levonorgestrel tablet) is not effective in terminating an existing pregnancy.
• Plan B One-Step (levonorgestrel tablet) does not protect against HIV-infection (AIDS) and other sexually transmitted diseases/infections.
• For women younger than age 17 years, Plan B One-Step (levonorgestrel tablet) is available only by prescription.

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenicity: There is no evidence of increased risk of cancer with short-term use of progestins. There was no increase in tumorgenicity following administration of levonorgestrel to rats for 2 years at approximately 5 μg/day, to dogs for 7 years at up to 0.125 mg/kg/day, or to rhesus monkeys for 10 years at up to 250 μg/kg/day. In another 7 year dog study, administration of levonorgestrel at 0.5 mg/kg/day did increase the number of mammary adenomas in treated dogs compared to controls. There were no malignancies.

Genotoxicity: Levonorgestrel was not found to be mutagenic or genotoxic in the Ames Assay, in vitro mammalian culture assays utilizing mouse lymphoma cells and Chinese hamster ovary cells, and in an in vivo micronucleus assay in mice.

Fertility: There are no irreversible effects on fertility following cessation of exposures to levonorgestrel or progestins in general.

Use In Specific Populations

Pregnancy

Many studies have found no harmful effects on fetal development associated with long-term use of contraceptive doses of oral progestins. The few studies of infant growth and development that have been conducted with progestin-only pills have not demonstrated significant adverse effects.

Nursing Mothers

In general, no adverse effects of progestin-only pills have been found on breastfeeding performance or on the health, growth, or development of the infant. However, isolated post-marketing cases of decreased milk production have been reported. Small amounts of progestins pass into the breast milk of nursing mothers taking progestin-only pills for long-term contraception, resulting in detectable steroid levels in infant plasma.

Pediatric Use

Safety and efficacy of progestin-only pills for long-term contraception have been established in women of reproductive age. Safety and efficacy are expected to be the same for postpubertal adolescents less than 17 years and for users 17 years and older. Use of Plan B One-Step (levonorgestrel tablet) emergency contraception before menarche is not indicated.

Geriatric Use

This product is not intended for use in postmenopausal women.

Race

No formal studies have evaluated the effect of race. However, clinical trials demonstrated a higher pregnancy rate in Chinese women with both Plan B and the Yuzpe regimen (another form of emergency contraception). There was a non-statistically significant increased rate of pregnancy among Chinese women in the Plan B One-Step (levonorgestrel tablet) trial. The reason for this apparent increase in the pregnancy rate with emergency contraceptives in Chinese women is unknown.

Hepatic Impairment

No formal studies were conducted to evaluate the effect of hepatic disease on the disposition of Plan B One-Step (levonorgestrel tablet) .

Renal Impairment

No formal studies were conducted to evaluate the effect of renal disease on the disposition of Plan B One-Step (levonorgestrel tablet) .

Last reviewed on RxList: 7/30/2009
This monograph has been modified to include the generic and brand name in many instances.