What Is Opill 28 Day? Uses, Dosage, and What You Need to Know in 2026

Opill 28 Day is a landmark medication in U.S. reproductive health history. It's the first daily oral contraceptive pill ever approved for over-the-counter (OTC) sale in the United States — meaning you can buy it without a prescription, without a doctor's visit, and without any age restriction.

But what exactly is Opill, how does it work, and is it right for you? This comprehensive guide covers everything you need to know.

What Is Opill 28 Day?

Opill 28 Day is a progestin-only oral contraceptive pill — sometimes called a "minipill" — manufactured by Perrigo. Its active ingredient is norgestrel 0.075 mg, a synthetic form of the hormone progesterone. Each 28-day pack contains 28 active tablets (no placebo pills).

The FDA approved Opill for OTC use on July 13, 2023 — and it became available on pharmacy shelves and online in March 2024. It is the first OTC birth control pill in the U.S. Importantly, norgestrel has been available as a prescription birth control pill since 1973 (originally under the name Ovrette), so its safety profile has been well established for over 50 years.

What Is Opill Used For?

Opill is FDA-approved to prevent pregnancy. It is not an emergency contraceptive — it does not work to prevent pregnancy after unprotected sex. It must be taken daily, starting before sexual activity, and works best with consistent use over time.

Some providers may also use progestin-only pills off-label for conditions like polycystic ovary syndrome (PCOS), endometriosis-related pain, or heavy menstrual periods — but these are off-label uses and you should speak with a healthcare provider before using Opill for anything other than pregnancy prevention.

How Effective Is Opill?

When taken exactly as directed — one pill at the same time each day, within a 3-hour window — Opill is approximately 98% effective at preventing pregnancy. This means that with perfect use, about 2 out of every 100 women using Opill for a year may become pregnant.

With typical use (which accounts for missed doses or late doses), effectiveness is approximately 91–93%. The 3-hour timing window is stricter than combination pills (which have a 12-hour window), making consistent daily timing especially important for Opill users.

How to Take Opill 28 Day: Dosage and Instructions

Dose: One tablet (0.075 mg norgestrel) taken by mouth once daily.

Timing: Take at the same time every day, within a 3-hour window. Set a daily alarm to help.

With or without food: Opill can be taken with or without food. Taking it at bedtime or with a meal may reduce nausea.

When to start: You can start Opill on any day of the month (except within 5 days of taking ulipristal acetate emergency contraception).

How soon it works: Opill takes 48 hours (2 days) to start working. Use backup contraception (condoms) for the first 2 days after starting.

No breaks: All 28 tablets are active. Start the next pack the day after finishing the last tablet with no gap.

Missed or late dose: If you take a pill more than 3 hours late, take it as soon as you remember and use backup contraception for 48 hours. If you miss a dose entirely, take it as soon as possible and use backup contraception for 48 hours.

Vomiting or diarrhea: If you vomit or have diarrhea within 4 hours of taking Opill, use backup contraception for 48 hours.

Who Can Use Opill?

Most people who menstruate and can become pregnant can safely use Opill. There is no age restriction. Opill is especially well-suited for:

People who cannot use estrogen-containing birth control (due to migraines with aura, high blood pressure, VTE history, or being a smoker over 35)

Breastfeeding people — progestin-only methods are generally considered safe while nursing

People who don't have easy access to a doctor's visit or prescription

Teens and young adults with no insurance or limited access to healthcare

Who Should NOT Use Opill?

Do not use Opill if you:

Have or have ever had breast cancer or other progestin-sensitive cancers

Are currently pregnant

Have active liver disease or liver tumors

Are currently using another hormonal birth control (pill, patch, ring, implant, injection, or hormonal IUD)

Have unexplained vaginal bleeding that you haven't discussed with a doctor

Are allergic to norgestrel, FD&C Yellow No. 5 (tartrazine), or other inactive ingredients

How Much Does Opill Cost and Where to Buy It

Opill costs $19.99 for a 28-pack (1-month supply), $49.99 for an 84-pack (3-month supply), and $89.99 for a 168-pack (6-month supply). It is available at CVS, Walgreens, Walmart, Target, Kroger, and online at opill.com, Amazon, and GoodRx. No prescription required.

If you have trouble finding Opill in stock locally, medfinder calls pharmacies near you to check real-time availability and texts you results.

Curious about how Opill works at a biological level? See our deep-dive on the mechanism of action of Opill.