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Kelnor 1/35 (28 Day)

Generic name: ethinyl estradiol and ethynodiol diacetate

Brand names: Kelnor 1/35 (28 Day), Valtya 1/50 (28 Day), Zovia 1/35 (28 Day), Zovia 1/50

Last updated November 2, 2026 0 views
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What is Kelnor 1/35 (28 Day)?

Kelnor 1/35 (28 Day) is a birth control pill that combines female hormones to stop ovulation (the release of an egg from an ovary). Kelnor 1/35 (28 Day) also changes your cervical mucus and the lining of your uterus, which makes it more difficult for sperm to reach the uterus and for a fertilized egg to attach to the uterus.

Kelnor 1/35 (28 Day) is used to prevent pregnancy.

Kelnor 1/35 (28 Day) may also be used for reasons not mentioned in this medication guide.

This section was rewritten for readability and reviewed for meaning.

How should I take birth control pills?

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

You will take your first pill on the first day of your period or on the first Sunday after your period begins. You may need to use back-up birth control, such as condoms or a spermicide, when you first start using this medication. Follow your doctor's instructions.

Take one pill every day, no more than 24 hours apart. When the pills run out, start a new pack the following day. You may get pregnant if you do not take one pill daily. Get your prescription refilled before you run out of pills completely.

Some birth control packs contain "reminder" pills to keep you on your regular cycle. Your period will usually begin while you are using these reminder pills.

You may have breakthrough bleeding, especially during the first 3 months. Tell your doctor if this bleeding continues or is very heavy.

Use a back-up birth control if you are sick with severe vomiting or diarrhea.

If you need major surgery or will be on long-term bed rest, you may need to stop using this medicine for a short time. Any doctor or surgeon who treats you should know that you are using birth control pills.

While taking birth control pills, you will need to visit your doctor regularly.

Store this medication at room temperature away from moisture and heat.

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Warnings

Do not use birth control pills if you are pregnant or if you have recently had a baby.

You should not use birth control pills if you have: uncontrolled high blood pressure, heart disease, coronary artery disease, circulation problems (especially with diabetes), undiagnosed vaginal bleeding, liver disease or liver cancer, severe migraine headaches, if you also take certain hepatitis C medication, if you will have major surgery, if you smoke and are over 35, or if you have ever had a heart attack, a stroke, a blood clot, jaundice caused by pregnancy or birth control pills, or cancer of the breast, uterus/cervix, or vagina.

Taking birth control pills can increase your risk of blood clots, stroke, or heart attack.

Smoking can greatly increase your risk of blood clots, stroke, or heart attack. You should not take birth control pills if you smoke and are over 35 years old.

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Before taking this medicine

Taking birth control pills can increase your chances of developing blood clots, having a stroke, or experiencing a heart attack. You are at a higher risk if you have high blood pressure, diabetes, high cholesterol, or if you are overweight. Your risk of stroke or blood clot is highest during the first year of taking birth control pills. Your risk is also high if you restart birth control pills after not taking them for 4 weeks or longer.

Smoking significantly raises your risk of blood clots, stroke, or heart attack. Your risk increases as you get older and the more you smoke. You should not take combination birth control pills if you smoke and are over 35 years old.

Do not use if you are pregnant. Stop taking Kelnor 1/35 (28 Day) and inform your doctor if you become pregnant or if you miss two menstrual periods in a row. If you have recently had a baby, wait at least 4 weeks before taking birth control pills.

You should not take birth control pills if you have:

  • untreated or uncontrolled high blood pressure;
  • heart disease (coronary artery disease, uncontrolled heart valve disorder, history of heart attack, stroke, or blood clot);
  • an increased risk of having blood clots due to a heart problem or a hereditary blood disorder;
  • circulation problems (especially if caused by diabetes);
  • a history of hormone-related cancer, or cancer of the breast, uterus/cervix, or vagina;
  • unusual vaginal bleeding that has not been checked by a doctor;
  • liver disease or liver cancer;
  • severe migraine headaches (with aura, numbness, weakness, or vision changes), especially if you are older than 35;
  • a history of jaundice caused by pregnancy or birth control pills;
  • if you smoke and are over 35 years old; or
  • if you take any hepatitis C medication containing ombitasvir/paritaprevir/ritonavir (Technivie).

To ensure that birth control pills are safe for you, inform your doctor if you have ever had:

  • heart disease, high blood pressure, or if you are prone to blood clots;
  • varicose veins;
  • high cholesterol or triglycerides, or if you are overweight;
  • depression;
  • migraine headaches;
  • diabetes, gallbladder disease;
  • seizures or epilepsy;
  • kidney disease;
  • irregular menstrual cycles;
  • tuberculosis; or
  • fibrocystic breast disease, lumps, nodules, or an abnormal mammogram.

The hormones in birth control pills can pass into breast milk and may harm a nursing baby. This medication may also reduce breast milk production. Do not use if you are breast-feeding a baby.

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Birth control pills side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Birth control pills may cause serious side effects. Stop using birth control pills and call your doctor immediately if you have:

  • signs of a stroke--sudden numbness or weakness (especially on one side of the body), sudden severe headache, slurred speech, problems with vision or balance;
  • signs of a blood clot--sudden vision loss, sharp chest pain, feeling short of breath, coughing up blood, pain or warmth in one or both legs;
  • heart attack symptoms--chest pain or pressure, pain spreading to your jaw or shoulder, nausea, sweating;
  • liver problems--loss of appetite, upper stomach pain, tiredness, fever, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
  • increased blood pressure--severe headache, blurred vision, pounding in your neck or ears;
  • swelling in your hands, ankles, or feet;
  • changes in the pattern or severity of migraine headaches;
  • a breast lump; or
  • symptoms of depression--sleep problems, weakness, feeling tired, mood changes.

Common side effects of Kelnor 1/35 (28 Day) may include:

  • nausea, vomiting (especially when you first start taking this medicine);
  • breast tenderness;
  • breakthrough bleeding;
  • acne, darkening of facial skin;
  • weight gain; or
  • problems with contact lenses.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

This section was rewritten for readability and reviewed for meaning.

What happens if I miss a dose?

Follow the instructions provided with your medicine. Ask your doctor or pharmacist if you do not understand these instructions. Missing a pill increases your risk of becoming pregnant.

If you miss one active pill, take two pills on the day you remember. Then take one pill each day for the rest of the pack.

If you miss two active pills in a row during Week 1 or 2, take two pills each day for two days in a row. Then take one pill each day for the rest of the pack. Use back-up birth control for at least 7 days after the missed pills.

If you miss two active pills in a row during Week 3, throw away the rest of the pack and start a new pack the same day if you are a Day 1 starter. If you are a Sunday starter, keep taking one pill each day until Sunday. On Sunday, throw away the rest of the pack and start a new pack that day.

If you miss three active pills in a row during Week 1, 2, or 3, throw away the rest of the pack and start a new pack on the same day if you are a Day 1 starter. If you are a Sunday starter, keep taking one pill each day until Sunday. On Sunday, throw away the rest of the pack and start a new pack that day.

If you miss two or more pills, you may not have a period that month. If you miss your period for two months in a row, call your doctor because you might be pregnant.

If you miss a reminder pill, throw it away and keep taking one reminder pill each day until the pack is empty.

This section was rewritten for readability and reviewed for meaning.

What happens if I overdose?

Seek emergency medical help or call the Poison Help line at 1-800-222-1222. Symptoms of an overdose may include nausea, vomiting, and vaginal bleeding.

Do not smoke while taking birth control pills, especially if you are older than 35 years.

Birth control pills will not protect you from sexually transmitted diseases, including HIV and AIDS. Using a condom is the only way to protect yourself from these diseases.

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What other drugs will affect birth control pills?

Other medicines can interact with birth control pills, including prescription drugs, over-the-counter medicines, vitamins, and herbal products. Some medicines can make birth control pills work less effectively, which could lead to pregnancy. Inform your doctor about all the medicines you are currently taking and any medicines you begin or stop using.

This section was rewritten for readability and reviewed for meaning.

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Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
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