From the Guidelines
Tri-Lo (norgestimate and ethinyl estradiol) is a combination oral contraceptive pill used for birth control, containing two hormones: norgestimate (a progestin) and ethinyl estradiol (an estrogen), with a typical dosage of one pill taken daily at the same time for 21 days, followed by 7 days of placebo pills or no pills. To use Tri-Lo effectively:
- Start on the first day of your menstrual period or as directed by your doctor.
- Take one pill daily at the same time each day.
- Use a backup method of contraception (e.g., condoms) for the first 7 days of your first pack.
- Continue taking pills in order, including during your period. Tri-Lo works by preventing ovulation, thickening cervical mucus, and altering the uterine lining. It's considered a low-dose pill, which may reduce side effects while maintaining effectiveness, as seen in studies such as 1. However, it may be less forgiving of missed doses compared to higher-dose pills. Always consult your healthcare provider for personalized advice and to discuss potential side effects or interactions with other medications. Some key points to consider when using Tri-Lo include:
- The risk of blood clots, which increases from 1 per 10,000 to 3 to 4 per 10,000 woman-years during COC use, as noted in 1.
- Common transient adverse effects of COCs include irregular bleeding, headache, and nausea, as discussed in 1.
- Drug interactions should also be avoided, with medications that decrease COC effectiveness (eg, anticonvulsants and antiretroviral drugs), as mentioned in 1. It's essential to follow the prescribed dosage and consult your healthcare provider for any concerns or questions, as they can provide personalized guidance and help you make informed decisions about your birth control options, based on the most recent and highest quality studies, such as 1.
From the FDA Drug Label
Each of the following products is a combination oral contraceptive containing the progestational compound norgestimate and the estrogenic compound ethinyl estradiol. Norgestimate is designated as (18,19-Dinor-17-pregn-4-en-20-yn-3-one,17-(acetyloxy)-13-ethyl-, oxime,(17α)-(+)-) and ethinyl estradiol is designated as (19-nor-17α-pregna,1,3,5(10)-trien-20-yne-3,17-diol).
Tri-Lo is a combination oral contraceptive containing norgestimate (a progestin) and ethinyl estradiol (an estrogen) 2.
- It is used to prevent pregnancy in women of reproductive age 2.
- The active ingredients are norgestimate (0.25 mg) and ethinyl estradiol (0.035 mg) per tablet 2.
From the Research
Definition and Composition of Tri-Lo
- Tri-Lo is a type of oral contraceptive that contains a combination of norgestimate and ethinyl estradiol 3.
- Norgestimate is a progestin, and ethinyl estradiol is a synthetic estrogen 4, 5.
- The combination of these two hormones works to inhibit ovulation, preventing pregnancy 5.
Mechanism of Action
- The progestin component (norgestimate) helps to thicken cervical mucus, making it more difficult for sperm to reach the egg 5.
- The estrogen component (ethinyl estradiol) helps to regulate the menstrual cycle and prevent ovulation 4, 5.
- The combination of these two hormones also helps to reduce the risk of breakthrough bleeding and improve cycle control 6.
Uses and Benefits
- Tri-Lo is used to prevent pregnancy, as well as to treat moderate acne vulgaris in women 3.
- The use of Tri-Lo has been shown to be effective in reducing the symptoms of acne, including inflammatory lesions and total lesion count 3.
- Tri-Lo may also be used to regulate menstrual cycles and reduce the risk of menstrual disorders 4, 5.
Comparison to Other Oral Contraceptives
- Tri-Lo is a type of combined oral contraceptive (COC), which contains both estrogen and progestin components 4, 5.
- COCs are highly effective in preventing pregnancy, but may not be suitable for all women, particularly those with a history of cardiovascular disease or estrogen-related adverse effects 7.
- Progestin-only pills (POPs) are an alternative option for women who are ineligible for or choose not to use COCs 7.