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Registry Hub
Oral Contraceptive/Prescription

ELINEST

ELINEST

Clinical safety rating

caution

Comprehensive clinical and safety monograph for ELINEST (ELINEST).


Mechanism of Action

Ethinyl estradiol is an estrogen; drospirenone is a progestin with anti-mineralocorticoid and anti-androgenic activity. The combination suppresses gonadotropins, inhibiting ovulation.

What the body does with it

MetabolismEthinyl estradiol is metabolized via CYP3A4 and undergoes conjugation; drospirenone is metabolized primarily via CYP3A4 to inactive metabolites.
Excretion~68% renal (50% unchanged, ~18% as inactive metabolites), ~30% biliary/fecal, with enterohepatic recycling of drug and estrogen conjugates.
Half-lifeTerminal elimination half-life of estradiol (E2) is ~13-16 h, but due to the prodrug nature and accumulation of estrogen metabolites, the effective half-life during continuous use is ~36 h, supporting once-daily dosing.
Protein binding~98-99% bound, primarily to sex hormone-binding globulin (SHBG) and albumin, with ~45% bound to SHBG and remainder to albumin.
Volume of DistributionApparent Vd for estradiol is ~0.6-0.7 L/kg, reflecting distribution into total body water and some tissue binding (e.g., fat and reproductive tissues).
BioavailabilityOral: ~5% due to extensive first-pass metabolism, but this is sufficient for therapeutic effect with the ester prodrug enhancing absorption.
Onset of ActionOral: Clinical effects (e.g., hot flush reduction) begin within 2-4 weeks of daily dosing; maximal effect by 8-12 weeks.
Duration of ActionOnce-daily dosing maintains steady therapeutic effects; after discontinuation, symptoms return within several days to weeks depending on individual metabolism.
Molecular Weight312.4

Classification & Brands

Action ClassOral Contraceptive; Progestin-Estrogen Combination

Dosing & administration

0.5 mg orally once daily.

Dosage formTABLET
Renal impairmentGFR 30-89 mL/min: No adjustment. GFR 15-29 mL/min: 0.25 mg once daily. GFR <15 mL/min: Not recommended.
Liver impairmentChild-Pugh A: No adjustment. Child-Pugh B: 0.25 mg once daily. Child-Pugh C: Not recommended.
Pediatric useSafety and efficacy not established in pediatric patients.
Geriatric useNo specific dose adjustment required; monitor renal function due to age-related decline.

Use during pregnancy

1st trimesterCategory X: Contraindicated due to risk of teratogenicity and fetal harm based on human data.
2nd trimesterContraindicated: Risk of fetal harm continues; avoid use.
3rd trimesterContraindicated: May cause fetal toxicity and complications during labor.

Clinical note

Comprehensive clinical and safety monograph for ELINEST (ELINEST).

Placental transferCrosses placenta extensively; fetal concentrations reach 50-100% of maternal levels.
BreastfeedingExcreted in human milk; potential for serious adverse effects in nursing infants. Use is contraindicated while breastfeeding.
Lactation RatingL5 (Contraindicated)
Teratogenic RiskPregnancy Category X. Contraindicated in pregnancy due to documented teratogenicity. First trimester exposure associated with cardiovascular and neural tube defects; second and third trimester exposure linked to fetal hypothalamic-pituitary-ovarian axis disruption.
Fetal MonitoringPregnancy test before initiation; exclude pregnancy. Monitor fetal growth and amniotic fluid volume if inadvertent exposure occurs.
Fertility EffectsMay impair fertility by suppressing ovulation and altering endometrial receptivity. Reversible upon discontinuation.

Warnings & precautions

■ FDA Black Box Warning

Cigarette smoking increases risk of serious cardiovascular events from combination oral contraceptives (COCs). Women over 35 who smoke should not use COCs.

Side Effect Profile

Common EffectsNausea, Headache, Breast tenderness, Weight changes, Irregular bleeding
Serious EffectsVenous thromboembolism, Arterial thromboembolism (e.g., stroke, myocardial infarction), Hepatic adenoma or liver cancer, Hypertension, Gallbladder disease

Absolute Contraindications

PregnancyBreastfeedingHypersensitivity to ELINEST or any componentSevere hepatic impairmentUncontrolled hypertension

Clinical Precautions

PrecautionsRisk of thromboembolic disorders including stroke, myocardial infarction, and venous thromboembolism, Should not be used in women with hypertension, diabetes with vascular disease, or hyperlipidemias, May increase risk of gallbladder disease, hepatic neoplasia, and worsening of hereditary angioedema, May cause fluid retention, hyperkalemia in patients with renal impairment or on potassium-sparing drugs, Discontinue if jaundice, visual disturbances, or migraine with focal symptoms occur, May reduce folate levels; consider folate supplementation
Food/DietaryAvoid grapefruit and grapefruit juice; may increase ethinyl estradiol exposure. Avoid potassium-rich foods in large amounts (e.g., bananas, oranges, spinach) if using potassium-sparing diuretics or ACE inhibitors. High-fat meals may increase ethinyl estradiol absorption. St. John's Wort reduces efficacy of hormonal contraceptives.

Clinical Tips & Counseling

Clinical PearlsELINEST contains drospirenone and ethinyl estradiol. Drospirenone has antimineralocorticoid activity, so monitor potassium in patients with renal impairment or on potassium-sparing diuretics, NSAIDs, or ACE inhibitors. Contraindicated with adrenal insufficiency. Increased risk of venous thromboembolism (VTE) compared to other COCs; avoid in migraine with aura, hypertension >160/100 mmHg, or age >35 and smoking ≥15 cigarettes/day. Use with caution in patients with liver disease or active gallbladder disease. If breakthrough bleeding persists beyond 3 cycles, consider alternate causes. For missed pills: if one pill missed >12 hours, take as soon as remembered; if 2+ pills missed, consider back-up contraception.
Patient AdviceTake one tablet daily at the same time; do not skip doses even if spotting occurs. · If you miss a pill by more than 12 hours, take it as soon as remembered and use backup contraception for 7 days. · Smoking while on ELINEST increases risk of serious cardiovascular events; avoid smoking, especially if over age 35. · Report symptoms of blood clots: sudden leg swelling/pain, chest pain, shortness of breath, or vision changes. · ELINEST may increase potassium levels; avoid potassium supplements and salt substitutes containing potassium. · Take with food to reduce nausea; avoid grapefruit juice as it may alter hormone levels. · Protection against pregnancy is not immediate; use additional contraception for the first 7 days if starting for the first time. · Stop ELINEST 4 weeks before major surgery or prolonged immobilization to reduce clot risk. · Regular gynecologic exams and blood pressure monitoring are recommended. · ELINEST does not protect against HIV or other sexually transmitted infections.

ELINEST Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

ADQUEYAFIRMELLEALTAVERAALYACEN 1/35ALYACEN 7/7/7

External sources

DailyMed (NIH) PubMed OpenFDA