Plan B One-Step also is referred to as the morning-after pill. It is intended to prevent pregnancy after a known or suspected contraceptive failure, unprotected intercourse, or forced sex. It contains large amounts of levonorgestrel, a progestin hormone found in some birth control pills. Plan B One-Step may work by preventing the egg and sperm from meeting by delaying ovulation. It won’t disrupt an implanted pregnancy, but may prevent a newly formed life from implanting in the uterus.[1]

Plan B One-Step consists of one pill taken up to 72 hours after sex.[2] Side effects may include changes in your period, nausea, lower abdominal pain, fatigue, headache, and dizziness.[3] If your period is more than a week late, you may be pregnant from a prior sexual encounter. Plan B One-Step should not be taken during pregnancy or used as a routine form of birth control.[4]

There is evidence Plan B One-Step use may increase the risk for ectopic (tubal) pregnancy, a potentially life-threatening condition.[5] Women who have severe abdominal pain may have an ectopic (tubal) pregnancy, and should seek immediate medical attention.

It is reported Plan B One-Step may prevent an average of 84% of expected pregnancies.[6]

There is much that is unknown about Plan B One-Step including the following:

  • dependence on the drug[7]
  • overdose[8]
  • the effect it could have on women who have not started their period[9]
  • the effect it could have on postmenopausal women[[10]
  • liver disease[11]
  • kidney disease[12]
  • the way it interacts with other drugs[13]
  • its ability to cause a higher rate of pregnancy in Chinese women[14]

 

Footnotes

[1]“Plan B One-Step Prescribing Information: Mechanism of Action,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[2]“Plan B One-Step Prescribing Information: Indications and Usage,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[3]“Plan B One-Step Prescribing Information: Clinical Trials Experience,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[4]“Plan B One-Step Prescribing Information: Contraindications,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf and “Plan B One-Step Prescribing Information: Indications and Usage,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[5]“Plan B One-Step Prescribing Information: Ectopic Pregnancy,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[6]“Plan B One-Step Prescribing Information: Clinical Studies,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[7]“Plan B One-Step Prescribing Information: Drug Abuse and Dependence,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[8]“Plan B One-Step Prescribing Information: Overdose,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[9]“Plan B One-Step Prescribing Information: Specific Populations/Pediatric,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[10]“Plan B One-Step Prescribing Information: Specific Populations/Geriatric,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[11]“Plan B One-Step Prescribing Information: Specific Populations/Hepatic Impairment,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[12]“Plan B One-Step Prescribing Information: Specific Populations/Renal Impairment,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[13]“Plan B One-Step Prescribing Information: Drug-Drug Interactions,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[14]“Plan B One-Step Prescribing Information: Specific Populations/Race,” Barr Pharmaceuticals, last modified August 2009, http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf

[15]“ella Prescribing Information: Open-Label Study,” Watson Pharma, last modified April 2012, http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E

[16]“ella Prescribing Information: Mechanism of Action,” Watson Pharma, last modified April 2012, http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E

[17]Donna J. Harrison and James G. Mitroka, “Defining Reality: The Potential Role of Pharmacists in Assessing the Impact of Progesterone Receptor Modulators and Misoprostol in Reproductive Health,” The Annals of Pharmacotherapy 45, (January 2011): 115.

[18]Ibid.

[19]“ella Prescribing Information: Adverse Reactions,” Watson Pharma, last modified April 2012, http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E

[20]“ella Prescribing Information: Open-Label Study,” Watson Pharma, last modified April 2012, http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E

[21]“ella Prescribing Information: Fertility Following Use,” Watson Pharma, last modified April 2012, http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E

[22]“ella Prescribing Information: Contraindications,” Watson Pharma, last modified April 2012, http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E

[23]“ella Prescribing Information: Repeated Use,” Watson Pharma, last modified April 2012, http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E

[24]“ella Prescribing Information: Nursing Mothers,” Watson Pharma, last modified April 2012, http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E

[24]“ella Prescribing Information: Nursing Mothers,” Watson Pharma, last modified April 2012, http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E