What is the appropriate prescription for Plan B (levonorgestrel), an emergency contraceptive?

From the Guidelines

Plan B (levonorgestrel) should be prescribed as a single 1.5 mg tablet taken orally as soon as possible after unprotected intercourse or contraceptive failure, with no prescription needed as it is available over-the-counter without age restrictions in most locations. For maximum effectiveness, it should be taken within 72 hours (3 days) of unprotected sex, though it can be used up to 120 hours (5 days) afterward with decreasing effectiveness 1. The medication works primarily by preventing or delaying ovulation, and may also prevent fertilization or implantation. Plan B is not effective if a person is already pregnant and won't harm an existing pregnancy.

Key Points to Consider

• Side effects may include nausea, headache, fatigue, abdominal pain, and menstrual changes 1.
• A follow-up pregnancy test is recommended if menstruation doesn't occur within three weeks.
• Plan B should not replace regular contraception methods as it's less effective than consistent use of birth control pills, IUDs, or other contraceptive methods.
• It's essential to note that ulipristal acetate may have increased effectiveness over oral levonorgestrel at the end of the 5-day window of use and in heavier women, but levonorgestrel is still a highly effective option 1.
• The American Academy of Pediatrics recommends advance prescription for EC as part of routine adolescent care, and there are various methods available, including orally administered hormones and insertion of a copper IUD 1.

From the FDA Drug Label

Levonorgestrel Tablet, 1.5 mg Emergency Contraceptive One Tablet. One Step. ... When should I use levonorgestrel tablet? The sooner you take emergency contraception, the better it works You should use levonorgestrel tablet within 72 hours (3 days) after you have had unprotected sex.

The appropriate prescription for Plan B is one tablet of 1.5 mg levonorgestrel to be taken within 72 hours (3 days) after unprotected sex 2.

• The medication should be taken as soon as possible for maximum effectiveness.
• It is essential to note that levonorgestrel tablet is not intended for regular birth control and should only be used as an emergency contraceptive.

From the Research

Prescription for Plan B

The appropriate prescription for Plan B, a form of emergency contraception, can be determined based on the following information:

• Plan B is a levonorgestrel-only pill, available over the counter for women of all ages 3
• It is most effective when taken within 72 hours of unprotected sexual intercourse, with a reported efficacy of around 50% in preventing expected pregnancies 4
• Women who weigh more than 75 kg or have a body mass index greater than 25 kg/m(2) may have a higher risk of unintended pregnancy when using oral levonorgestrel emergency contraception, and alternative methods such as ulipristal acetate or copper intrauterine devices may be preferable in this setting 3
• The copper intrauterine device is the most effective method of emergency contraception, with a reported efficacy of over 95% in preventing pregnancies 4, 3

Key Considerations

Some key considerations for prescribing Plan B include:

• The patient's weight and body mass index, as these may affect the efficacy of the medication 3
• The timing of the unprotected sexual intercourse, as Plan B is most effective when taken within 72 hours 4, 3
• The patient's medical history and any potential interactions with other medications 3
• The availability of alternative methods of emergency contraception, such as ulipristal acetate or copper intrauterine devices 4, 3

Administration

Plan B can be administered as a single dose, with the newly approved single-dose formulation, Plan B One-Step, simplifying use 5

• The medication should be taken as soon as possible after unprotected sexual intercourse, ideally within 72 hours 4, 3
• Women who are already pregnant should not take Plan B, as it will not terminate an existing pregnancy 6, 7