Plan B One-Step (levonorgestrel 1.5 mg) Dailymed

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.

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. 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.

Plan B One-Step is not effective in terminating an existing pregnancy.

Some women may experience spotting a few days after taking Plan B One-Step. 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.

A physical examination is not required prior to prescribing Plan B One-Step. 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.

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

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.

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.

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 trial. The reason for this apparent increase in the pregnancy rate with emergency contraceptives in Chinese women is unknown.

Emergency contraceptive pills are not effective if a woman is already pregnant. Plan BOne-Step is believed to act as an emergency contraceptive principally by preventing ovulation or fertilization (by altering tubal transport of sperm and/or ova). In addition, it may inhibit implantation (by altering the endometrium). It is not effective once the process of implantation has begun.

Emergency contraceptive pills are not effective if a woman is already pregnant. Plan B  One-Step is believed to act as an emergency contraceptive principally by preventing ovulation or fertilization (by altering tubal transport of sperm and/or ova). In addition, it may inhibit implantation (by altering the endometrium). It is not effective once the process of implantation has begun.

Absorption Following a single dose administration of Plan B One-Step in 30 women under fasting conditions, maximum plasma concentrations of levonorgestrel of 19.1 ng/mL were reached at 1.7 hours. See Table 2. Table 2. Pharmacokinetic Parameter Values Following Single Dose Administration of Plan B One-Step (levonorgestrel) tablet 1.5 mg to 30 Healthy Female Volunteers under Fasting Conditions Mean (± SD) Cmax (ng/mL) AUCt (ng·hr/mL)N=29 AUCinf (ng·hr/mL) Tmax (hr)median (range) t1/2 (hr) Levonorgestrel 19.1 ( 9.7) 294.8 ( 208.8) 307.5( 218.5) 1.7 (1.0-4.0) 27.5 ( 5.6) Cmax = maximum concentrationAUCt = area under the drug concentration curve from time 0 to time of last determinable concentrationAUCinf = area under the drug concentration curve from time 0 to infinityTmax = time to maximum concentrationt1/2 = elimination half life Effect of Food: The effect of food on the rate and the extent of levonorgestrel absorption following single oral administration of Plan B One-Step has not been evaluated. Distribution The apparent volume of distribution of levonorgestrel is reported to be approximately 1.8 L/kg. It is about 97.5 to 99% protein-bound, principally to sex hormone binding globulin (SHBG) and, to a lesser extent, serum albumin. Metabolism Following absorption, levonorgestrel is conjugated at the 17β-OH position to form sulfate conjugates and, to a lesser extent, glucuronide conjugates in plasma. Significant amounts of conjugated and unconjugated 3α, 5β-tetrahydrolevonorgestrel are also present in plasma, along with much smaller amounts of 3α, 5α-tetrahydrolevonorgestrel and 16βhydroxylevonorgestrel. Levonorgestrel and its phase I metabolites are excreted primarily as glucuronide conjugates. Metabolic clearance rates may differ among individuals by several-fold, and this may account in part for the wide variation observed in levonorgestrel concentrations among users. Excretion About 45% of levonorgestrel and its metabolites are excreted in the urine and about 32% are excreted in feces, mostly as glucuronide conjugates. Specific Populations Pediatric This product is not intended for use in the premenarcheal population, and pharmacokinetic data are not available for this population. Geriatric This product is not intended for use in postmenopausal women, and pharmacokinetic data are not available for this population. 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 trial. The reason for this apparent increase in the pregnancy rate with emergency contraceptives in Chinese women is unknown [see USE IN SPECIFIC POPULATIONS (8.6)]. Hepatic Impairment No formal studies were conducted to evaluate the effect of hepatic disease on the disposition of Plan B One-Step. Renal Impairment No formal studies were conducted to evaluate the effect of renal disease on the disposition of Plan B One-Step. Drug-Drug Interactions No formal drug-drug interaction studies were conducted with Plan B One-Step [see DRUG INTERACTIONS (7)].

Take Plan B One-Step 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, in order to be evaluated for an ectopic pregnancy. After taking Plan B One-Step, 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 as routine contraception. Plan B One-Step is not effective in terminating an existing pregnancy. Plan B One-Step does not protect against HIV-infection (AIDS) and other sexually transmitted diseases/infections. For women younger than age 17 years, Plan B One-Step is available only by prescription.