What is Norgestimate-Ethinyl Estradiol Triphasic: Uses, Warnings & Interactions

Updated Jun 25, 2025  •  Published Dec 30, 2020

Triphasic norgestimate-ethinyl estradiol is a generic oral contraceptive also available in several brand-name versions. The active ingredients are an estrogen (estradiol) and a progestin (norgestimate). The pills are “triphasic” because they come in three dosage strengths. Each dosage strength is taken for one week during the cycle. Triphasic norgestimate-ethinyl estradiol also comes in a low estrogen formulation.

Norgestimate-Ethinyl Estradiol Triphasic overview

BRAND NAMES:

  • Tri-Estarylla, Tri-Femynor, Tri-Lo-Estarylla, Tri-Lo-Marzia, Tri-Lo-Mili, Trinessa, Tri-Sprintec

Generic Names:

  • Norgestimate-ethinyl estradiol triphasic

Uses:

  • Prevents pregnancy.

Therapeutic Classes:

  • Oral contraceptive, triphasic contraceptive combination

Forms:

  • Tablet

How it’s taken:

  • By mouth

What is Norgestimate-Ethinyl Estradiol Triphasic used for?

Triphasic norgestimate-ethinyl estradiol prevents pregnancy.  

What form(s) does Norgestimate-Ethinyl Estradiol Triphasic come in

  • Tablets

    • 0.18 mg norgestimate / 0.035 mg ethinyl estradiol | 0.215 mg/0.035 mg | 0.25 mg/0.035 mg

    • 0.18/ 0.025 | 0.215 mg/0.025 mg | 0.25 mg/0.025 mg

What are common Norgestimate-Ethinyl Estradiol Triphasic doses?

  • For the prevention of pregnancy: One tablet daily for 28 days

Common Norgestimate-Ethinyl Estradiol Triphasic prescriptions

  • Norgestim-Eth Estrad Triphasic
    1 package (28 tablets), 0.18-35/0.215-35/0.25-35mg-mcg disp pack

  • Norgestim-Eth Estrad Triphasic
    28 tablets disp pack

How to take Norgestimate-Ethinyl Estradiol Triphasic

  • Please read and follow the Instructions for Use that come with this medicine.

  • The prescriber will tell you when to take the first pill.

    • It will either be on the day your period starts or the first Sunday after your period starts. 

    • When switching from another type of hormonal birth control, take the first pill the day you would have started a new blister pack, replaced a vaginal ring or patch, or the day an implant or IUD is removed.

  • Take one pill daily at the same time each day. Do not miss doses.

    • The first week of pills consists of seven active gray pills in the top row of the blister pack. 

    • The second week of pills consists of seven active light blue pills in the second row. 

    • The third week of pills consists of seven active blue pills in the third row. 

    • The last week of pills consists of seven inactive white pills in the bottom row.

    • When the last white pill is taken, start a new blister pack of pills the next day.

    • You should always start a new pack on the same day of the week each cycle. 

  • Take tablets at the same time each day without regard to food.

  • Swallow the tablet whole with a drink of water.

  • If you vomit or have diarrhea three to four hours after taking a tablet, take a similarly colored pill from your extra blister pack.

    • If you don’t have an extra blister pack, take the next pill in the current blister pack and finish the blister pack. 

    • If you vomit or have diarrhea for longer than one day, continue through the current blister pack but use additional birth control until contacting the prescriber.

  • Store the tablets at room temperature in the original carton. Protect from light.

What to do if you miss a dose of Norgestimate-Ethinyl Estradiol Triphasic

  • Do not miss doses. Forgetting doses increases the risk of pregnancy.

  • If a colored pill is missed:

    • Take it as soon as possible. 

    • Take the next dose at its regular time.

    • You can take two doses in a single day to make up for a missed dose. 

    • Pregnancy is not a risk, so you don’t need backup birth control.

  • If you miss two colored pills in a row in the first two weeks:

    • Take two pills on the day you remember and two pills the next day.

    • Missing two pills in a row increases the risk of pregnancy. Use backup birth control for at least seven days.

  • If you miss two blue pills in a row in the third week: 

    • Immediately start a new blister pack if you are a Day 1 starter.

    • If you are a Sunday starter, continue to take the blister pack pills until Sunday. Start a new pack on Sunday. Use backup birth control. 

    • You can get pregnant in the first seven days of starting a new kit. Use backup birth control for the first seven days.

  • If you miss three or more colored pills in a row in any week:

    • Start a new blister pack if you are a Day 1 starter.

    • If you are a Sunday starter, continue to take pills from the current blister pack until Sunday. Start a new pack on Sunday. Use backup birth control.

    • You can get pregnant for the first seven days after starting a new blister pack. Use backup birth control.

  • If you’re not sure if you missed a dose, use backup birth control.  

Norgestimate-Ethinyl Estradiol Triphasic contraindications

  • This medicine is not right for everyone. 

  • Do not use norgestimate-ethinyl estradiol if you are:

    • Pregnant

    • Older than 35 and smoke

    • Older than 35 have focal headaches or migraines with aura

  • Do not use norgestimate-ethinyl estradiol if you have blood clot problems, a history of blood clot problems, or risk factors for blood clots:

    • Coronary artery disease

    • Cerebrovascular disease

    • Uncontrolled high blood pressure

    • Diabetes with blood vessel problems

    • Certain types of heart valve problems

  • Norgestimate-ethinyl estradiol is also contraindicated in women with:

    • Uterine bleeding that has not been checked by a doctor

    • Liver disease or liver tumors

    • Current or past breast cancer that is hormone-sensitive

Norgestimate-Ethinyl Estradiol Triphasic warnings

  • Tell any healthcare provider or other healthcare provider who treats you that you are using this medicine. 

    • This drug can alter the results of important blood tests.

    • Doses may need to stop at least two weeks before surgery and should not restart until four weeks after surgery. 

  • Keep all appointments with the prescriber.

  • Immediately tell the prescriber if you become pregnant, think you’re pregnant, or miss two periods in a row. 

  • Before starting birth control pills, make sure the prescriber knows if you are pregnant or breastfeeding, or have recently given birth.

  • Tell the prescriber if you smoke or if you have:

    • Heart or blood vessel problems

    • High blood pressure

    • Diabetes

    • High cholesterol

    • Migraines

    • Depression

    • A history of face, neck, and throat swelling (angioedema)

  • Also tell the prescriber if you’ve had problems during pregnancy, particularly:

    • Skin yellowing (jaundice) 

    • Brown patches on your face (chloasma)

  • Combination birth control pills can cause serious problems, including:

    • Increased risk of blood clots, heart attack, and stroke

    • Increased risk of breast or cervical cancer

    • Liver problems

    • Gallbladder problems

    • High blood pressure

    • High cholesterol and fats

    • Severe or long-lasting headaches

  • You may have no bleeding or only a little bleeding during your period. If it is accompanied by pregnancy symptoms (like morning sickness) or happens two months in a row, talk to the prescriber.

    • If you miss two periods in a row, you will need a pregnancy test.

  • Birth control pills can darken skin on the face. Use sunscreen and avoid exposure to the sun or tanning lights.

  • This medicine will not protect you from HIV/AIDS or other sexually transmitted diseases. 

  • Birth control pills may decrease milk production in nursing women.

Norgestimate-Ethinyl Estradiol Triphasic interactions

  • Do not take norgestimate-ethinyl estradiol with any hepatitis C drug containing ombitasvir/paritaprevir/ritonavir.

  • To avoid potentially hazardous drug interactions, tell the prescriber about all the prescription drugs, over-the-counter medications, and supplements regularly taken, particularly: 

  • Avoid grapefruit and grapefruit juice when taking norgestimate-ethinyl estradiol.

  • Tell other healthcare providers you are using this medicine before they prescribe new medications.

Norgestimate-Ethinyl Estradiol Triphasic side effects

Serious side effects

Talk to a healthcare provider if you notice any signs or symptoms of a possible serious side effect,  including:

  • Symptoms of a blood clot:

    • Persistent leg pain, particularly in the calf

    • Sudden changes or loss of vision

    • Numbness or weakness on one side of your body, sudden or severe headache, vision problems, trouble walking, trouble speaking

    • Chest pain, chest tightness, trouble breathing, coughing up blood

  • Yellow skin or eyes, dark urine, clay-colored stools, appetite loss, fatigue

  • Breast lumps, breast tenderness, breast pain 

  • Stomach pain, nausea, vomiting

  • Worsening or new depression

  • Allergic reaction: Rash, hives, itching, facial, mouth, tongue, or throat swelling, trouble breathing

Some potentially serious side effects may not have symptoms, so regular clinic visits are required to spot these problems:

  • High blood pressure

  • High cholesterol and fats

Less serious side effects

  • Headache

  • Painful periods

  • Nausea and vomiting

  • Breast problems, tenderness, nipple pain

  • Mood changes

  • Acne

  • Vaginal discharge

  • Vaginal infection

  • Light spotting or bleeding between periods

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