Zafemy (norelgestromin / ethinyl estradiol) is a birth control patch you apply to your skin once a week. It contains two hormones (estrogen and progesterone) that work together to prevent pregnancy. If you use it perfectly, it's 99% effective. You can place the patch on your upper arm, stomach, buttock, or back. But if you weigh more than 198 pounds or have a body mass index or BMI of 30 kg/m² or higher, it might not work as well. Some people might experience side effects like sore breasts, headaches, or a rash at the application site.
To prevent pregnancy
Zafemy (norelgestromin / ethinyl estradiol) is a combination of two hormones: norelgestromin (a progestin) and ethinyl estradiol (an estrogen). These two hormones work together to help prevent pregnancy by:
Stopping ovulation (release of an egg from the ovary)
Changing cervical mucus to block sperm movement
Creating an unfriendly environment for the fertilized egg by changing the lining in the uterus (womb)
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
Patch is applied once a week
99% effective at preventing pregnancy when used perfectly
Patch stayed on the skin for 95% of people in studies
Raises your risk for serious blood clots
More estrogen is absorbed compared to other combination birth control pills, which might cause more side effects
Might not work as well for people who weigh more than 198 pounds or have a BMI of 30 kg/m² or higher
Zafemy (norelgestromin / ethinyl estradiol) helps prevent pregnancy, but it doesn't protect you from human immunodeficiency virus (HIV), hepatitis, or other sexually transmitted diseases (STIs). Using a condom with Zafemy (norelgestromin / ethinyl estradiol) can help lower your changes of getting an STI.
Try to apply your Zafemy (norelgestromin / ethinyl estradiol) patch on the same day each week. Setting a reminder or alarm can help you remember.
If you forget to change your Zafemy (norelgestromin / ethinyl estradiol) patch, talk to your prescriber or pharmacist. What you need to do next depends on which week of the cycle you're in and how long you forgot. You might also need to use backup birth control for a certain period.
Don't try to use a Zafemy (norelgestromin / ethinyl estradiol) patch again if it's not sticky anymore, if it's folded up, if it's dirty, or if it's come loose. Don't use tape, adhesives, or wraps to hold the patch in place. Instead, just put on a new patch right away.
It's normal to have some irregular bleeding while using Zafemy (norelgestromin / ethinyl estradiol). This doesn't mean it's not working. Keep using it as directed. Talk to your gynecologist if your bleeding doesn’t stop or if you miss your period.
Let your gynecologist know if you feel depressed or your mood gets worse while using Zafemy (norelgestromin / ethinyl estradiol). If symptoms become severe, they might have you stop it.
Tell your gynecologist if you notice swelling or sudden weight gain while using Zafemy (norelgestromin / ethinyl estradiol). Discuss your medical history before starting this medication.
Zafemy (norelgestromin / ethinyl estradiol) can interact with many medications. Tell your healthcare team about all prescription, over the counter, and supplement products you take before starting this medication.
To throw away a used Zafemy (norelgestromin / ethinyl estradiol) patch, fold it in half so the sticky sides stick together. This prevents accidental exposure to leftover medication. Used patches can be dangerous if children or pets chew or swallow them because they still have some medication in them.
Zafemy (norelgestromin / ethinyl estradiol) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Over 35 years old who smoke cigarettes
Smoking cigarettes while using Zafemy (norelgestromin / ethinyl estradiol) can significantly raise your risk for blood clots. These blood clots can lead to more serious problems, such as heart attack and stroke. The risk is greater if you're over 35 years old and have a history of smoking cigarettes. If you smoke, talk with your gynecologist about safer birth control alternatives.
Risk factors: Age 35 or older and smoke | Recent surgery with a long period of bed rest | Starting Zafemy (norelgestromin / ethinyl estradiol) less than a month after childbirth | High blood pressure | People with BMI at or greater than 30 kg/m² | High cholesterol | Diabetes | Higher dose of estrogen
Compared to other combined hormonal contraceptives, Zafemy (norelgestromin / ethinyl estradiol) leads to higher estrogen absorption, which might raise the risk of side effects, including serious blood clots. These clots can occur anywhere in your body, including your lungs (pulmonary embolism or PE), legs (deep vein thrombosis or DVT), brain (stroke), and heart (heart attack). Get emergency help right away if you have any signs of a blood clot.
Brain: weakness or numbness in your arms, legs, or face on one side of the body, trouble speaking, blurred vision, dizziness, loss of balance, trouble walking, or confusion
Eyes: trouble seeing, bulging eye, double vision
Heart: chest pain, sweating, nausea, or dizziness
Lungs: trouble breathing, chest pain, or cough
Legs: cramps, swelling, pain, or muscle tightness
If you need to have surgery, tell your care team you're taking Zafemy (norelgestromin / ethinyl estradiol). They might have you stop taking it 4 weeks before until 2 weeks after your surgery to lower your risk of blood clots. If you recently delivered a baby, you shouldn't start Zafemy (norelgestromin / ethinyl estradiol) until 4 weeks after delivery if you're not breastfeeding your child.
Risk factors: Using hormonal contraceptives for more than 8 years
Don't use Zafemy (norelgestromin / ethinyl estradiol) if you have liver problems, such as hepatitis, severe cirrhosis, or liver tumors. Although rare, this medication can raise your risk of benign liver tumors. If you notice signs of liver problems, stop using Zafemy (norelgestromin / ethinyl estradiol) and talk to your gynecologist about other birth control options. Signs of liver problems include jaundice (yellowing of the skin or whites of the eyes), fever, tiredness, loss of appetite, or dark urine.
Risk factors: Older age | Using hormonal contraceptives for a long time | History of high blood pressure
Zafemy (norelgestromin / ethinyl estradiol) can raise your blood pressure. The risk is higher if you're older and have been using birth control for a long time. If you have a history of high blood pressure that's well-controlled, your prescriber might monitor you while you use Zafemy (norelgestromin / ethinyl estradiol). If you have concerns, talk with them about the risks and benefits of using this medication.
Risk factors: History of gallbladder problems
Some studies show that Zafemy (norelgestromin / ethinyl estradiol) can slightly raise your risk of gallbladder problems. And if you already have gallbladder problems, this medication could make them worse. If you’ve had cholestasis (a liver condition that slows or stops bile flow) from birth control or pregnancy before, you might have a higher risk of getting it again with Zafemy (norelgestromin / ethinyl estradiol). Talk to your prescriber if you have a history of gallbladder or liver problems before using this medication.
Risk factors: Prediabetes or diabetes | High triglycerides
Zafemy (norelgestromin / ethinyl estradiol) can raise your blood sugar and triglycerides levels. If you have prediabetes or diabetes, your prescriber will likely monitor your blood sugar while you take this medication. High triglycerides can lead to a higher risk of pancreatitis (inflammation of the pancreas). Speak with your gynecologist before starting Zafemy (norelgestromin / ethinyl estradiol) if you have a history of high blood sugar or triglycerides. They might suggest a different birth control option or monitor your lab work more closely while you're using this medication.
Let your gynecologist know if you experience new or worsening migraines or headaches while using Zafemy (norelgestromin / ethinyl estradiol). If you develop frequent, severe, or new headaches, you might need to stop the medication.
People who use Zafemy (norelgestromin / ethinyl estradiol) can sometimes experience breakthrough bleeding or spotting. If this happens, talk to your gynecologist to rule out pregnancy, infections, or other medical conditions. If no serious cause is found, the bleeding might stop over time or after switching to a different birth control.
In clinical trials, most people started their withdrawal bleeding on the fourth day of the patch-free week, lasting about 5 to 6 days. If you have concerns about irregular bleeding, talk to your gynecologist.
Risk factors: History of depression
If you have a history of depression, your prescriber will monitor you while using Zafemy (norelgestromin / ethinyl estradiol). If your depression gets worse or becomes serious, they might stop the medication. Let your prescriber know if you experience mood changes, sadness, or loss of interest in activities while taking this medication.
Risk factors: History of breast or cervical cancer | Taking COCs for a long time
Study results are mixed, but Zafemy (norelgestromin / ethinyl estradiol) and other combined hormonal birth control pills might raise your risk for breast and cervical cancer.
Don't take Zafemy (norelgestromin / ethinyl estradiol) if you currently have or have had breast cancer because some types of breast cancer grow faster in the presence of estrogen, which is in this medication. Perform breast self-checks regularly at home and get yearly breast exams with your gynecologist to help with early detection. Let them know if you notice any new or abnormal lumps, pain, or swelling in your breasts.
Make sure you follow up with your gynecologist to get proper screenings for cervical cancer. Report any signs of vaginal bleeding or discharge that's not normal.
Risk factors: History of hereditary angioedema | History of chloasma gravidarum
If you have certain conditions, such as hereditary angioedema or chloasma (a skin condition that causes dark patches on the face), talk to your prescriber before taking Zafemy (norelgestromin / ethinyl estradiol) because it might worsen your symptoms. If you have a history of chloasma, limit exposure to the sun or UV light while taking Zafemy (norelgestromin / ethinyl estradiol).
Zafemy (norelgestromin / ethinyl estradiol) follows a 28-day (4-week) cycle. Each patch releases 150 mcg of norelgestromin and 35 mcg of ethinyl estradiol per day.
Weeks 1 to 3: The typical dose is to apply 1 new patch to your skin once a week on the same day each week. Be sure to take off the old patch before applying a new one.
Week 4: Don't apply a patch this week. This is your patch-free week (three weeks on, one week off).
Over 35 years old who smoke
Currently have or have had a blood clot
Blood clotting condition
Certain heart rhythm problems, like atrial fibrillation (AFib)
High blood pressure that's not under control
Diabetes with high blood pressure or organ damage
Any migraine headaches for those over 35 years old
Have a body mass index (BMI) at or greater than 30 kg/m²
Liver problems or liver disease
Unexplained vaginal bleeding that hasn't been diagnosed
Currently have or have had breast cancer
Take hepatitis C combination medications containing ombitasvir/paritaprevir/ritonavir
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AvKARE. (2023). Zafemy- norelgestromin and ethinyl estradiol patch [package insert]. DailyMed.
French, V. (2024). What to know about skipping periods with birth control. The American College of Obstetricians and Gynecologists.
Latwal, B., et al. (2020). Authorized generics vs. branded generics: A perspective. Journal of Generic Medicines.
MedlinePlus. (2024). Cholestasis.
Planned Parenthood. (n.d.). How effective is the birth control patch?
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