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Combined birth control pills (ethinyl estradiol with a progestin)

Brand names: Loestrin, Junel, Microgestin, Sprintec, Yaz

Combined birth control pills contain an estrogen and a progestin. They prevent pregnancy and can also ease heavy, painful periods and acne.

Brand namesLoestrin, Junel, Microgestin, Sprintec, Yaz
Type of medicineHormonal birth control
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

Taken correctly, they are very effective. They don't protect against STIs.

There are many brands and types; this page covers what they have in common.

What it's used for

  • Preventing pregnancy
  • Heavy or painful periods
  • Acne
  • PCOS symptoms
  • Endometriosis pain

How to take it

  • Take one pill every day at about the same time.
  • Follow your pack's instructions for when to start and what to do with the inactive pills.
  • If you vomit within a few hours of a pill or have severe diarrhea, use backup birth control as your label explains.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Spotting between periods (often in the first months)
  • Nausea
  • Breast tenderness
  • Headache
  • Mood changes
Call 911Chest pain, sudden shortness of breath, or coughing blood (possible clot in the lung)
Call 911Weakness on one side, trouble speaking, sudden vision loss, or the worst headache of your life
Call your provider todayPain, swelling, or warmth in one leg
Call your provider todayYellow skin or eyes
Call your provider todayNew migraines with aura, or much worse headaches

Warnings

  • Boxed warning: smoking raises the risk of serious heart and blood vessel problems, especially over age 35. Don't smoke.
  • Not for people with migraines with aura, past clots or stroke, some heart and liver problems, or very high blood pressure.

Other medicines, foods, and alcohol

  • Rifampin, some seizure medicines, St. John's wort, and some HIV medicines make it less effective; use backup.
  • It can lower lamotrigine levels.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Stop taking it if you become pregnant. Ask your provider about birth control while breastfeeding.

Missed doses, overdose, and storage

If you miss a dose

Missed-pill rules depend on the type and how many pills you missed. Check the leaflet that came with your pack, and use backup birth control (like condoms) until your pharmacist or provider says you're covered. Emergency contraception may be an option.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.