Backup Plan Onestep (Levonorgestrel) belongs to the family of medications known as progestins. Progestins are female sex hormones that are used in birth control pills and often in combination with the hormone estrogen.

Backup Plan Onestep (Levonorgestrel) is a progestin-only emergency birth control pill intended for use within 72 hours of unprotected sexual intercourse. It should only be used by women whose regular birth control methods have failed or who may have had intercourse without birth control. It is not a substitute for correct use of regular birth control.

Backup Plan Onestep (Levonorgestrel) is believed to prevent pregnancy primarily by delaying ovulation or preventing fertilization of the egg. It may also prevent implantation of the egg by altering the endometrium (inner lining of the uterus). It is important to realize that once implantation has occurred and pregnancy is established, Backup Plan Onestep (Levonorgestrel) cannot cause an abortion or harm the fetus. No serious complications have been reported with Backup Plan Onestep (Levonorgestrel).

Backup Plan Onestep (Levonorgestrel) reduces the risk of pregnancy among users from around 8% to around 1% after unprotected sexual intercourse. It is most effective in the first 24 hours after intercourse.

It should be noted that this medication does not protect against HIV infection (AIDS) or other sexually transmitted infections.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. As well, some forms of Backup Plan Onestep (Levonorgestrel) may not be used for all of the conditions discussed here. If you have not discussed this with your doctor or are not sure why you are taking Backup Plan Onestep (Levonorgestrel), speak to your doctor. Do not stop taking Backup Plan Onestep (Levonorgestrel) without consulting your doctor.

Do not give Backup Plan Onestep (Levonorgestrel) to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The 1.5 mg tablet contained in the kit should be taken as soon as possible within 72 hours of unprotected sexual intercourse. The medication is most effective if taken within 12-24 hours of unprotected sexual intercourse.

Because Backup Plan Onestep (Levonorgestrel) is often associated with nausea, your doctor may also want you to take medication to prevent nausea at the same time as taking these pills. If you vomit within 2 hours of taking the tablet, you should contact your health care provider as you may need to take another dose. Backup Plan Onestep (Levonorgestrel) can be used at any time during the menstrual cycle. It can be taken with or without food. Taking it with food may help reduce the nausea.

Most women have their expected menstrual period within 7 days of their normal time after using this medication. If you don't have your menstrual period within 7 days of when it is expected, you should have a pregnancy test done.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take this medication exactly as recommended by your doctor. Backup Plan Onestep (Levonorgestrel) is not intended to be used routinely as birth control.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Backup Plan Onestep (Levonorgestrel). If you are concerned about side effects, discuss the risks and benefits of Backup Plan Onestep (Levonorgestrel) with your doctor.

The following side effects have been reported by at least 1% of people taking Backup Plan Onestep (Levonorgestrel). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• abdominal pain
• breast tenderness
• Diarrhea
• dizziness
• fatigue
• headache
• irregular, altered, or heavier menstrual bleeding
• migraine
• nausea
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• cramping or severe abdominal pain before your next normal period
• itching
• painful menstruation
• skin rash
• vaginal discharge
• very heavy vaginal bleeding

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Backup Plan Onestep (Levonorgestrel).

Each round, biconvex, white tablet with "C" debossed on one side and "1" on the other side, contains 1.5 mg of Backup Plan Onestep (Levonorgestrel). Nonmedicinal ingredients: microcrystalline cellulose PH102, lactose monohydrate fast flow, croscarmellose sodium, poloxamer 188, and magnesium stearate vegetable.

Do not take Backup Plan Onestep (Levonorgestrel) if you:

• are allergic to Backup Plan Onestep (Levonorgestrel) or any ingredients of Backup Plan Onestep (Levonorgestrel)
• are or may be pregnant
• have undiagnosed abnormal vaginal bleeding

There may be an interaction between Backup Plan Onestep (Levonorgestrel) and any of the following:

• acitretin
• antibiotics (ampicillin, cotrimoxazole, Tetracycline, clarithromycin)
• Apixaban
• Aprepitant
• barbiturates (e.g., pentobarbital, Phenobarbital)
• Bosentan
• cannabis
• Carbamazepine
• Cholestyramine
• Colestipol
• Clobazam
• Cobicistat
• Cyclosporine
• dabigatran
• Dabrafenib
• darunavir
• Deferasirox
• diabetes medications (e.g., Canagliflozin, Glyburide, insulin, Metformin, Rosiglitazone)
• Edoxaban
• efavirenz
• Eslicarbazepine
• Exenatide
• fosaprepitant
• fosphenytoin
• Heparin
• HIV protease inhibitors (e.g., atazanavir, indinavir, ritonavir, saquinavir)
• Isotretinoin
• Lamotrigine
• low-molecular-weight heparins (e.g., Dalteparin, Enoxaparin, Tinzaparin)
• lumacaftor and Ivacaftor
• mifepristone
• Modafinil
• mycophenolate
• nevirapine
• Octreotide
• Oxcarbazepine
• Perampanel
• Phenytoin
• primidone
• rifampin
• rifabutin
• Rivaroxaban
• St. John's wort
• Sarilumab
• Selegiline
• siltuximab
• thalidomide
• Tocilizumab
• Topiramate
• Tranexamic acid
• Triazolam
• tretinoin
• Ulipristal
• Voriconazole
• Warfarin

Because only one tablet of Backup Plan Onestep (Levonorgestrel) is taken, the effects of these medications on how the  Backup Plan Onestep (Levonorgestrel) works is likely to be minimal. If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Backup Plan Onestep (Levonorgestrel). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, decongestants, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.