What Is Nortrel 1/35 21 Day? Uses, Dosage, and What You Need to Know in 2026

Nortrel 1/35 21 Day is a combination oral contraceptive (birth control pill) widely prescribed in the United States. Whether you've been recently prescribed it or you're researching your birth control options, this complete guide tells you exactly what Nortrel 1/35 21 Day is, what it does, and how to take it correctly.

What Is Nortrel 1/35 21 Day?

Nortrel 1/35 21 Day is a combination oral contraceptive manufactured by Teva Pharmaceuticals USA. It belongs to the class of medications known as estrogen-progestin contraceptives. The name "1/35" refers to the doses of the two active hormones in each yellow active tablet:

Norethindrone 1 mg — a synthetic progestin (a type of progesterone)

Ethinyl estradiol 0.035 mg (35 mcg) — a synthetic estrogen

The "21 Day" refers to the pack format: 21 active (yellow) tablets containing hormones. Unlike a 28-day pack, the 21-day pack does not include placebo tablets — after taking all 21 active tablets, you take no pills for 7 days, then start a new pack.

What Is Nortrel 1/35 21 Day Used For?

Nortrel 1/35 21 Day is FDA-approved for one primary use: prevention of pregnancy. It is NOT approved or indicated for emergency contraception. However, like most combination OCPs, it may provide additional benefits:

More regular, lighter, and less painful periods

Reduced risk of ovarian cysts

Possible improvement in acne (this effect varies by formulation)

Nortrel 1/35 does NOT protect against sexually transmitted infections (STIs), including HIV.

How Effective Is Nortrel 1/35 21 Day at Preventing Pregnancy?

When taken correctly and consistently (perfect use), combination oral contraceptives like Nortrel 1/35 are more than 99% effective at preventing pregnancy. With typical use (accounting for occasional missed pills and human error), effectiveness is approximately 91–93%. This means about 7–9 out of 100 women using the pill typically may experience an unintended pregnancy in a year of use.

How Do You Take Nortrel 1/35 21 Day? Step-by-Step Dosage Instructions

The 21-day regimen works on a "3 weeks on, 1 week off" cycle:

Start day: Begin taking on the first Sunday after your period starts (Sunday Start) or on the first day of your period (Day 1 Start). If using Sunday Start, use backup contraception for the first 7 days.

Active phase: Take one yellow active tablet every day for 21 days at the same time each day, no more than 24 hours apart.

Pill-free week: After completing all 21 tablets, take NO pills for 7 days. Your withdrawal bleed (period) will usually occur during this week.

New pack: After the 7-day break, start a new pack of 21 tablets — even if your period hasn't ended yet.

What If You Miss a Pill?

If you miss one active tablet: Take it as soon as you remember — even if that means taking two tablets in one day. Continue taking one tablet daily. You do not need backup contraception if only one pill was missed.

If you miss two or more active tablets in a row: Take the most recent missed tablet as soon as you remember. Take the next tablet at the usual time (even if that's two tablets in one day). Use backup contraception (condoms) for 7 days. If you missed pills in Week 3 or missed 3+ pills, talk to your provider about whether you should finish the pack or start a new one.

Is Nortrel 1/35 a Controlled Substance?

No. Nortrel 1/35 21 Day is not a controlled substance. It does not have a DEA schedule. It is a prescription medication, but it can be prescribed by any licensed healthcare provider (OB/GYN, PCP, NP, PA) and is widely available via telehealth platforms. There are no refill restrictions beyond standard prescription renewal requirements.

Who Should Not Take Nortrel 1/35 21 Day?

Nortrel 1/35 is not appropriate for everyone. You should not take it if you:

Smoke cigarettes and are 35 years of age or older

Have had blood clots, a stroke, or a heart attack

Have uncontrolled high blood pressure

Have liver disease or liver tumors

Are pregnant or suspect you may be pregnant

For a deeper look at potential side effects, see Nortrel 1/35 21 Day Side Effects: What to Expect and When to Call Your Doctor. To understand how it works in your body, see How Does Nortrel 1/35 21 Day Work? Mechanism of Action Explained.