What are the dosing options for Levonorgestrel (progestin) and Ethinyl Estradiol (estrogen) tablets, a combined oral contraceptive (COC)?

From the Guidelines

Levonorgestrel and ethinyl estradiol tablets are typically available in several dosing options for oral contraception, with the most recent guidelines recommending a standard regimen of 0.1 mg levonorgestrel with 20 mcg ethinyl estradiol, or 0.15 mg levonorgestrel with 30 mcg ethinyl estradiol 1. The standard regimen involves taking one active pill daily for 21 days, followed by 7 days of placebo pills or no pills (during which withdrawal bleeding occurs). Some key points to consider when prescribing levonorgestrel and ethinyl estradiol tablets include:

• Extended-cycle regimens are also available, where active pills are taken continuously for 84 days followed by 7 days of placebo or low-dose ethinyl estradiol pills.
• Some formulations offer continuous dosing with 365 days of active pills to eliminate monthly bleeding entirely.
• For optimal contraceptive effectiveness, pills should be taken at approximately the same time each day.
• If a pill is missed, specific instructions should be followed based on how many pills were missed and when in the cycle the miss occurred.
• These various regimens offer flexibility to accommodate different preferences regarding menstrual frequency while maintaining contraceptive efficacy.
• The combination of hormones works by preventing ovulation, thickening cervical mucus to block sperm, and thinning the uterine lining to prevent implantation. It's also important to consider the potential risks and benefits of levonorgestrel and ethinyl estradiol tablets, including the increased risk of blood clots and stroke, particularly in women with certain medical conditions or risk factors 1. Overall, the choice of dosing option for levonorgestrel and ethinyl estradiol tablets will depend on individual patient needs and preferences, and should be guided by the most recent clinical guidelines and evidence-based recommendations 1.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION To achieve maximum contraceptive effectiveness, Kariva® must be taken exactly as directed and at intervals not exceeding 24 hours. Kariva® may be initiated using either a Sunday start or a Day 1 start. One white tablet is taken daily for 21 days, followed by 1 light-green (inert) tablet daily for 2 days and 1 light-blue (active) tablet daily for 5 days For all subsequent cycles, the patient then begins a new 28-tablet regimen on the next day (Sunday) after taking the last light-blue tablet. If a patient misses 1 white tablet, she should take the missed tablet as soon as she remembers. If the patient misses 2 consecutive white tablets in Week 1 or Week 2, the patient should take 2 tablets the day she remembers and 2 tablets the next day; thereafter, the patient should resume taking 1 tablet daily until she finishes the cycle pack The patient should be instructed to use a back-up method of birth control if she has intercourse in the 7 days after missing pills.

The dosing options for levonorgestrel and ethinyl estradiol tablets and ethinyl estradiol tablets oral contraceptive are as follows:

• Sunday Start: One white tablet daily for 21 days, followed by 1 light-green (inert) tablet daily for 2 days and 1 light-blue (active) tablet daily for 5 days
• Day 1 Start: One white tablet daily for 21 days, one light-green (inert) tablet daily for 2 days followed by 1 light-blue (ethinyl estradiol) tablet daily for 5 days Key points:
• Take one tablet daily at the same time
• Do not exceed 24 hours between tablets
• Use a back-up method of birth control if pills are missed 2

From the Research

Dosing Options for Levonorgestrel and Ethinyl Estradiol Tablets

• The combined oral contraceptive pill is an effective contraceptive method that can also offer other benefits, and pills containing levonorgestrel or norethisterone in combination with ethinyloestradiol 35 microgram or less are considered first-line 3.
• The lowest dose with the least side-effects is the overriding principle of prescribing, and it is essential to spend time teaching patients and partners how to manage their pill-taking and to be responsible for their medication and prevention follow up 4.
• Older COCs with norethisterone or levonorgestrel have a lower risk for venous thromboembolism (VTE) than newer COCs with desogestrel, drospirenone, or gestodene 5.

Ethinyl Estradiol Tablets Oral Contraceptive

• The risk of venous thrombosis (VT) varies according to the type of progestogen that is found in combined oral contraceptives (COCs), and when combined with the estrogen component ethinylestradiol (EE), the androgenic progestogens are better able to counteract the EE-induced stimulation of liver proteins and hence are associated with a twofold decreased risk of VT compared with non- or antiandrogenic progestogens 6.
• The use of a levonorgestrel intrauterine device was not associated with an increased risk of venous thrombosis, while injectable depot-medroxyprogesterone acetate contraceptives were associated with a 3.6-fold increased risk of venous thrombosis compared with nonusers of hormonal contraceptives 7.

Key Considerations

• Prescribe a pill with the lowest effective dose of oestrogen and progestogen, and consider the patient's individual risk factors for venous thromboembolism 3, 5.
• The progestogen levonorgestrel seems to be associated with the lowest risk of VT, especially in women with inherited thrombophilia 6.
• Other nonoral contraceptives, such as progestogen-only contraceptives, combined vaginal rings, and patches, may have different risks of VT, but there is insufficient evidence to compare these methods with COCs 6.