How does this medication work? What will it do for me?

Norethindrone acetate - ethinyl estradiol belongs to the class of medications called oral contraceptives (birth control pills). It is an estrogen (ethinyl estradiol) and progestin (norethindrone) combination pill used for the prevention of pregnancy.

Norethindrone acetate - ethinyl estradiol works by preventing ovulation (the release of an egg from an ovary) and by causing changes in the mucus of the cervix which make it difficult for sperm to penetrate and for an egg to implant in the wall of the uterus.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. As well, some forms of this medication 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 this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication 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.

What form(s) does this medication come in?

Each green, round, unscored tablet debossed with "b" on one side and "155" on the other side contains norethindrone acetate 1.5 mg and ethinyl estradiol 30 µg. Nonmedicinal ingredients: acacia, D&C Yellow No. 10, FD&C Blue No. 1, FD&C Yellow No. 6, lactose, magnesium stearate, starch, sugar, and talc.

Each pale orange tablet contains no active ingredients. Nonmedicinal ingredients: lactose, ferrous fumarate, alcohol SD3A anhydrous 200 and SD3A 190, gluten (from corn starch), acacia gum, confectioner's sugar, magnesium stearate, purified water, and talc.

How should I use this medication?

21-day pack: Take 1 tablet daily for 21 days, then take no pills for 7 days.

28-day pack: Take 1 tablet daily for 21 days, then 1 "reminder" pill daily for 7 days.

See the package insert for information on when to start and what to do if you forget to take a pill.

Talk with your doctor about the best time to start your pills. The first day of your menstrual period (bleeding) is known as "Day 1." Your doctor may have you start your pills on the first Sunday after your period starts or on Day 1 of your period. The pills should be taken approximately the same time every day.

It may be advisable to use a second method of birth control (e.g., latex condoms and spermicidal foam or gel) for the first 7 days of the first cycle of pill use.

Many women have spotting or light bleeding or may feel sick to their stomach during the first 3 months taking the pill. If you do feel sick, do not stop taking the pill. The problem will usually go away. If it does not go away, check with your doctor or clinic.

If you experience vomiting or diarrhea, or if you take certain medications (such as antibiotics), your pills may not work as well. Use a backup method, such as latex condoms and spermicidal foam or gel, until you can check with your doctor or clinic.

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 very important to take this medication exactly as prescribed by your doctor. If you miss pills at any time the risk of becoming pregnant increases.

If you miss one pill, take it as soon as you remember, and take the next pill at the usual time. This means that you might take 2 pills in one day.

If you miss 2 pills in a row during the first 2 weeks of your cycle, take 2 pills the day you remember and 2 pills the next day, then take one pill a day until you finish the pack. Use a second method of birth control if you have sex in the 7 days after you miss the pills.

If you miss 2 pills in a row during the third week of your cycle or 3 or more pills in a row anytime in your cycle and you start your pills on Sunday, keep taking one pill a day until Sunday. On Sunday, safely discard the rest of the pack and start a new pack that day. You may not have a period this month. If you miss 2 periods in a row, call your doctor or clinic.

If you miss 2 pills in a row during the third week of your cycle or 3 or more pills at anytime during your cycle and you start your pills on Day 1, safely dispose of the rest of the pill pack and start a new pack that same day. Use another method of birth control if you have sex in the 7 days after you miss the pills. You may not have a period this month. If you miss 2 periods in a row, call your doctor or clinic.

If you are not sure what to do after missing pills, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

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.

Who should NOT take this medication?

Do not take this mediction if you:

  • are allergic to norethindrone acetate, to ethinyl estradiol, or to any of the ingredients of the medication
  • are or may be pregnant
  • have eye damage resulting from blood vessel disease of the eye, such as a partial or complete loss of vision
  • have had a heart attack or coronary artery disease
  • have, have had, or may have breast cancer
  • have liver disease
  • have or have had benign or malignant liver tumours
  • have or have had cerebrovascular disorders (e.g, stroke)
  • have or have had thrombophlebitis or thromboembolic disorders (blood clotting problems)
  • have or may have a tumour dependent on estrogen
  • have undiagnosed abnormal vaginal bleeding

What side effects are possible with this medication?

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 this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. 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 cramping or bloating
  • acne (usually less common after 3 months of treatment, and may improve if acne already exists)
  • breast pain, tenderness, or swelling
  • brown, blotchy spots on exposed skin
  • dizziness
  • gain or loss of body or facial hair
  • increased or decreased interest in sexual intercourse
  • increased sensitivity of skin to sunlight
  • nausea
  • swelling of ankles and feet
  • unusual tiredness or weakness
  • vomiting
  • weight gain or loss

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

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

  • changes in the uterine bleeding pattern during or between periods, such as:
    • decreased bleeding during periods
    • breakthrough bleeding or spotting between periods
    • prolonged bleeding at periods
    • complete stopping of menstrual bleeding that occurs over several months in a row
    • stopping of menstrual bleeding that only occurs sometimes
  • depression
  • headaches or migraines
  • increased blood pressure
  • swelling, pain, or tenderness in upper abdominal area
  • vaginal infection with vaginal itching or irritation, or thick, white, or curd-like discharge

Stop taking this medication and seek medical attention immediately if any of the following side effects occur:

  • abdominal or stomach pain (sudden, severe, or continuing)
  • coughing up of blood
  • headache (severe or sudden)
  • loss of coordination (sudden)
  • loss of vision or change in vision (sudden)
  • pains in chest, groin, or leg (especially in calf of leg)
  • shortness of breath (sudden or unexplained)
  • slurring of speech (sudden)
  • weakness, numbness, or pain in arm or leg (unexplained)

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 this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Breast cancer: Increasing age and a strong family history of breast cancer are the most significant risk factors for the development of breast cancer. Other established risk factors include obesity, not having had children, and a late age at first full-term pregnancy. The identified groups of women that may be at increased risk of developing breast cancer before menopause are women who have used birth control pills for more than 8 years or who started using them at an early age. For a few women, the use of birth control pills may accelerate the growth of an existing but undiagnosed breast cancer.

If you are taking birth control pills, learn how to perform a breast self-examination. Notify your doctor any time you detect a lump. A yearly clinical breast examination is also recommended because, if breast cancer develops, medications that contain estrogen may cause a rapid progression.

Depression: If you have had clinical depression in the past, you may be more likely to experience it again while taking this medication.

Diabetes: Current low-dose birth control pills affect glucose control very little. If you have diabetes or a family history of diabetes, monitor your blood glucose closely to detect any worsening of blood sugar control after starting birth control pills.

Eyes: Women who are pregnant or who take birth control pills may experience fluid build-up in the cornea of the eye, which may cause visual disturbances and changes in tolerance to contact lenses, especially rigid contact lenses. Wearers of soft contact lenses usually do not experience difficulties. If you experience visual changes or alterations in tolerance to contact lenses, you may need to stop wearing the lenses temporarily or permanently.

Fibroids: If you have fibroids (leiomyomata), your doctor should closely monitor your condition. If sudden enlargement, pain, or tenderness occurs, contact your doctor to see if you need to stop taking the medication.

Heart disease: Cigarette smoking increases the risk of serious heart disease and death. Taking birth control pills increases this risk, especially with increasing age. Studies show evidence that women who smoke and are over 35 years old should not use birth control pills.

Other women who have a high risk for heart disease include those with diabetes, high blood pressure, or abnormal cholesterol levels, or a family history of any of these conditions. Whether taking birth control pills increases this risk is unclear.

For low-risk, non-smoking women of any age, the benefits of birth control pill use outweigh the possible cardiovascular risks of low-dose pills.

Regular check-ups: You should have a yearly physical examination and follow-up visit with your doctor.

Return to fertility: After stopping birth control therapy, you should delay pregnancy until at least one normal menstrual cycle has occurred in order to date the pregnancy. An alternative birth control method (e.g., condoms) should be used during this time.

If you do not menstruate for 6 months or more after stopping birth control pills, notify your doctor.

Sexually transmitted infections: Birth control pills do not protect against sexually transmitted infections, including HIV/AIDS. For protection against these, use latex condoms.

Pregnancy: Pregnant women should not take birth control pills. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: The use of birth control pills while breast-feeding is not recommended. The hormones in the medication pass into breast milk and may reduce its quantity and quality. The long-term effects on the developing child are not known.

What other drugs could interact with this medication?

There may be an interaction between norethindrone acetate - ethinyl estradiol and any of the following:

  • acetaminophen
  • aminocaproic acid
  • ampicillin
  • anti-diabetes medications (e.g., insulin)
  • antihypertensive medications (medications that are used to treat high blood pressure)
  • barbiturates (e.g., butalbital, phenobarbital)
  • benzodiazepines (e.g., diazepam, lorazepam)
  • caffeine
  • carbamazepine
  • chloral hydrate
  • chloramphenicol
  • clofibrate
  • clomipramine
  • clonidine
  • corticosteroids (e.g., hydrocortisone, prednisone)
  • cotrimoxazole
  • cyclosporine
  • ethosuximide
  • folic acid
  • glutethimide
  • griseofulvin
  • meperidine
  • meprobamate
  • metronidazole
  • neomycin
  • nitrofurantoin
  • penicillin
  • phenothiazines (e.g., chlorpromazine, perphenazine)
  • phenytoin
  • primidone
  • protease inhibitors (e.g., nelfinavir, ritonavir)
  • rifampin
  • succinylcholine sulfonamides (e.g., sulfamethoxazole)
  • tetracyclines (e.g., minocycline, tetracycline)
  • theophylline
  • topiramate
  • vitamin B12
  • warfarin

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 this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, 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.