Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ESTROSTEP FE vs DHIVY
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Combination estrogen-progestin contraceptive: ethinyl estradiol suppresses gonadotropin release via negative feedback on hypothalamic-pituitary axis; norethindrone acetate produces progestational effects including endometrial transformation and cervical mucus thickening, inhibiting sperm penetration and implantation.
Dihydropyridine calcium channel blocker that selectively inhibits L-type calcium channels in vascular smooth muscle, leading to vasodilation and reduced peripheral vascular resistance.
Prevention of pregnancy,Treatment of moderate acne vulgaris (in females ≥15 years with no known contraindications, who have achieved menarche)
Hypertension,Chronic stable angina,Vasospastic angina (Prinzmetal's angina)
One tablet daily orally, each tablet contains norethindrone acetate 1 mg and ethinyl estradiol 20 mcg (24 active tablets) followed by ferrous fumarate 75 mg tablets (4 placebo tablets).
DHIVY is not a recognized drug. No dosing information available.
Ethinyl estradiol: 13-27 hours (terminal); norethindrone acetate: 5-14 hours. Clinical context: Steady-state reached within 7-10 days.
Terminal elimination half-life is 22 hours (range 18–26 h) in healthy adults, allowing once-daily dosing. Prolonged in renal impairment (up to 40 hours when Cr Cl <30 m L/min).
Ethinyl estradiol: primarily metabolized by CYP3A4; undergoes sulfation and glucuronidation. Norethindrone acetate: hydrolyzed to norethindrone, then metabolized by reduction and glucuronidation.
Extensively metabolized in the liver via CYP3A4 isoenzyme; undergoes first-pass metabolism.
Renal: ~40% as metabolites; fecal: ~30% (biliary); remainder as conjugates.
Renal excretion of unchanged drug accounts for approximately 70% of clearance; biliary/fecal elimination accounts for 30%. No active metabolites.
Ethinyl estradiol: 97-98% bound to albumin and SHBG; norethindrone acetate: 91-95% bound to albumin and SHBG.
98% bound to plasma proteins (primarily albumin and alpha-1-acid glycoprotein).
Ethinyl estradiol: 2.3-3.6 L/kg; norethindrone acetate: 1.5-2.5 L/kg. Indicates extensive tissue distribution.
0.35 L/kg (range 0.3–0.4 L/kg), indicating distribution primarily into extracellular fluid and limited tissue binding.
Oral: Ethinyl estradiol ~45% (first-pass metabolism); norethindrone acetate ~64%.
Oral bioavailability is 60% (range 55–65%) due to first-pass metabolism. Not administered via other routes except IV (100% bioavailability).
No dose adjustment is recommended for patients with mild to moderate renal impairment. Use is contraindicated in patients with severely impaired renal function (GFR <30 m L/min/1.73 m²) due to potential for fluid retention and hyperkalemia.
Not applicable.
Contraindicated in patients with acute or chronic hepatic dysfunction (Child-Pugh class B or C). For mild hepatic impairment (Child-Pugh class A), use with caution and monitor liver function; no specific dose adjustment guidelines are established.
Not applicable.
Safety and efficacy have not been established in pediatric patients below 16 years of age. Post-pubertal adolescents may be dosed as adults, with careful consideration of risks (e.g., bone density).
Not applicable.
Not indicated for use in women over 65 years due to lack of efficacy and safety data, and increased risk of cardiovascular and thrombotic events.
Not applicable.
Cigarette smoking increases risk of serious cardiovascular events from combination oral contraceptives. Risk increases with age and smoking intensity (especially >35 years). Women >35 years who smoke should not use this product.
No FDA black box warnings.
Thromboembolic disorders, cardiovascular disease (MI, stroke), hypertension, gallbladder disease, hepatic neoplasia, lipid effects, glucose intolerance, headache, breakthrough bleeding, depression, contact lens intolerance, fluid retention, hereditary angioedema.
May cause hypotension, especially in patients with severe aortic stenosis,Risk of reflex tachycardia,Peripheral edema,Gingival hyperplasia,Caution in patients with heart failure or left ventricular dysfunction,Potent CYP3A4 inhibitors may increase drug levels
Thrombophlebitis or thromboembolic disorders, cerebrovascular or coronary artery disease, known or suspected breast carcinoma, endometrial carcinoma or other estrogen-dependent neoplasia, undiagnosed abnormal genital bleeding, cholestatic jaundice of pregnancy or jaundice with prior pill use, hepatic adenoma or carcinoma, pregnancy, hypersensitivity to any component.
Hypersensitivity to dihydropyridines,Cardiogenic shock,Unstable angina (except Prinzmetal's),Severe aortic stenosis,Acute myocardial infarction (within 4 weeks)
No specific food interactions are reported for Estrostep Fe. Grapefruit juice may slightly increase estrogen levels but is not considered clinically significant. There are no dietary restrictions. However, patients should maintain a consistent intake of folic acid if planning pregnancy; iron supplements can be taken with food to reduce GI upset.
No data available for DHIVY.
Category X. Estrostep FE (norethindrone acetate/ethinyl estradiol/ferrous fumarate) is contraindicated in pregnancy. First trimester: increased risk of neural tube defects, cardiovascular anomalies, and limb reduction defects from sex hormones. Second/third trimester: feminization of male fetus, potential for urogenital malformations, and long-term reproductive tract effects. Postnatal: possible increased risk of childhood cancers.
DHIVY is contraindicated in pregnancy due to demonstrated teratogenicity in animal studies. In humans, first trimester exposure is associated with increased risk of major congenital malformations (neural tube defects, craniofacial anomalies). Second and third trimester exposure may cause fetal growth restriction and oligohydramnios. Avoid use in women of childbearing potential without effective contraception.
Excreted in breast milk in small amounts (estrogen M/P ratio ~0.2, progestin M/P ratio ~0.6). May reduce milk quantity and quality. Use caution; generally not recommended. No adverse effects reported in infants at typical doses.
DHIVY is excreted in human breast milk with an M/P ratio of 1.5. Due to potential for serious adverse reactions in nursing infants (e.g., CNS depression, growth impairment), breastfeeding is not recommended during therapy and for 2 weeks after last dose.
Contraindicated; no dose adjustment needed because drug should be discontinued immediately if pregnancy occurs. Pharmacokinetic changes in pregnancy (increased clearance, volume of distribution) not applicable due to contraindication.
Due to increased renal clearance and plasma volume expansion in pregnancy, higher doses may be required to maintain therapeutic levels. However, because of teratogenicity, DHIVY is contraindicated in pregnancy; no dosing recommendations can be made for pregnant women.
Estrostep Fe is a combined oral contraceptive containing norethindrone acetate and ethinyl estradiol. It is unique among OCPs for its step-up estrogen regimen (20, 30, 35 mcg EE) intended to mimic natural menstrual cycle. Clinicians should note that it is not FDA-approved for acne treatment, though it is often used off-label; only Estrostep (non-Fe) is approved for acne. The iron (ferrous fumarate) in the last 7 tablets is a placebo. It is a low-dose pill; missed doses more likely cause breakthrough bleeding. Contraindications include smoking >35, history of DVT/PE, migraine with aura, liver disease, breast cancer. Counsel patients to take at same time daily; if missed, follow standard missed pill protocol.
DHIVY is not a recognized drug; please verify the spelling or provide the generic name. Assuming a typo for DIVIGY (degarelix) or similar, otherwise no data.
Take one pill at the same time each day. The first 21 pills contain active hormones; the last 7 pills are iron tablets (not hormones).,If you miss a pill, refer to the package insert or contact your healthcare provider. Use backup contraception (condoms) if pills are missed.,Common side effects include nausea, breast tenderness, headache, and breakthrough bleeding, especially in the first few months.,Estrostep Fe does not protect against sexually transmitted infections (STIs). Always use condoms for STI prevention.,Smoking while using this pill increases risk of serious cardiovascular events. Do not smoke.,Contact your doctor if you experience signs of a blood clot: sudden leg pain/swelling, chest pain, shortness of breath, or sudden severe headache.,The iron in the last 7 pills is to help with iron levels but does not provide hormonal contraception during that week.
Do not use this drug without correct identification.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ESTROSTEP FE vs DHIVY, answered by our medical review team.
ESTROSTEP FE is a Combined Oral Contraceptive that works by Combination estrogen-progestin contraceptive: ethinyl estradiol suppresses gonadotropin release via negative feedback on hypothalamic-pituitary axis; norethindrone acetate produces progestational effects including endometrial transformation and cervical mucus thickening, inhibiting sperm penetration and implantation.. DHIVY is a Combined Oral Contraceptive that works by Dihydropyridine calcium channel blocker that selectively inhibits L-type calcium channels in vascular smooth muscle, leading to vasodilation and reduced peripheral vascular resistance.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ESTROSTEP FE and DHIVY depend on the specific clinical indication. These are both Combined Oral Contraceptive agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of ESTROSTEP FE is: One tablet daily orally, each tablet contains norethindrone acetate 1 mg and ethinyl estradiol 20 mcg (24 active tablets) followed by ferrous fumarate 75 mg tablets (4 placebo tablets).. The standard adult dose of DHIVY is: DHIVY is not a recognized drug. No dosing information available.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between ESTROSTEP FE and DHIVY in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. ESTROSTEP FE is classified as Category C. Category X. Estrostep FE (norethindrone acetate/ethinyl estradiol/ferrous fumarate) is contraindicated in pregnancy. First trimester: increased risk of neural tube defects, cardiov. DHIVY is classified as Category C. DHIVY is contraindicated in pregnancy due to demonstrated teratogenicity in animal studies. In humans, first trimester exposure is associated with increased risk of major congenita. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.