Comparative Pharmacology
Head-to-head clinical analysis: ORTHO TRI CYCLEN 21 versus ORTHO NOVUM 1 50 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORTHO TRI CYCLEN 21 versus ORTHO NOVUM 1 50 21.
ORTHO TRI-CYCLEN 21 vs ORTHO-NOVUM 1/50 21
Head-to-head clinical comparison of therapeutic indices and safety profiles.
Combination estrogen-progestin oral contraceptive; suppresses gonadotropin secretion (FSH, LH) via negative feedback, preventing ovulation; increases cervical mucus viscosity and alters endometrial receptivity.
Combination oral contraceptive consisting of mestranol (estrogen) and norethindrone (progestin). Mestranol is converted to ethinyl estradiol, which suppresses gonadotropin release (FSH, LH) from the pituitary, inhibiting ovulation. Norethindrone induces changes in cervical mucus (increasing viscosity) and endometrial lining, creating a hostile environment for sperm implantation.
Prevention of pregnancy
Prevention of pregnancy
One tablet daily for 21 days, followed by 7 days of placebo, then repeat. Each tablet contains 0.180 mg norgestimate and 0.035 mg ethinyl estradiol (days 1–7), 0.215 mg/0.035 mg (days 8–14), and 0.250 mg/0.035 mg (days 15–21). Oral route.
One tablet orally once daily for 21 days, followed by 7 tablet-free days. Each tablet contains 1 mg norethindrone and 50 mcg mestranol.
None Documented
None Documented
Norgestimate: ~24 hours (terminal); ethinyl estradiol: ~17 hours (terminal). Steady-state achieved within 5-7 days; clinical significance: missed doses may increase contraceptive failure risk.
Norethindrone: biphasic terminal half-life 7-9 hours for parent compound, 8-11 hours for metabolites; clinical steady-state achieved after 5-7 days.
Norgestimate: hydrolyzed to norelgestromin and norgestrel; metabolized by CYP3A4, CYP2C9, and CYP2C19. Ethinyl estradiol: metabolized by CYP3A4 and undergoes glucuronidation.
Mestranol is rapidly demethylated to ethinyl estradiol, primarily by CYP2C9 and CYP3A4. Ethinyl estradiol and norethindrone undergo hepatic metabolism via CYP3A4, with conjugation and excretion in urine and feces.
Renal: ~70% (metabolites, primarily glucuronide and sulfate conjugates of norgestimate and ethinyl estradiol); Fecal: ~30% (biliary elimination of unchanged drug and metabolites).
Renal 50-60% as glucuronide and sulfate conjugates of norethindrone and mestranol/metabolites; fecal 20-30% via biliary elimination.
Norgestimate: ~99% bound to albumin and SHBG; ethinyl estradiol: ~98% bound to albumin; norethindrone (active metabolite) binds with similar high affinity.
Norethindrone: 97-98% bound to albumin and sex hormone-binding globulin (SHBG); mestranol: 95-97% bound to albumin.
Norgestimate: Vd ~6-8 L/kg; ethinyl estradiol: Vd ~3-5 L/kg. Large Vd indicates extensive tissue distribution including breast, uterine, and hepatic tissues; clinical relevance: potential for drug interactions (e.g., enzyme inducers).
Norethindrone: Vd 3-4 L/kg (approx. 210-280 L for 70 kg adult), indicating extensive tissue distribution; mestranol: Vd 1.5-2 L/kg.
Oral: Norgestimate ~75% (first-pass metabolism limits bioavailability); ethinyl estradiol ~40-60% (substantial first-pass effect).
Norethindrone: oral bioavailability 40-60% due to first-pass metabolism; mestranol rapidly converted to ethinyl estradiol with oral bioavailability 40-50%.
No specific dose adjustment is provided in manufacturer labeling; use with caution in patients with renal impairment. GFR-based adjustments are not established.
No dose adjustment required for mild to moderate renal impairment. Insufficient data for severe renal impairment (GFR < 30 mL/min); use with caution.
Contraindicated in patients with hepatic disease or hepatocellular carcinoma. Child-Pugh class B or C: contraindicated. Child-Pugh class A: use with caution, no specific dose adjustment defined.
Contraindicated in Child-Pugh class B or C (moderate to severe hepatic impairment). For Child-Pugh class A, use with caution and monitor liver function.
Safety and efficacy established in postmenarchal females; dosing is same as adult: one tablet daily for 21 days. Weight-based dosing not applicable.
Not indicated for use before menarche. Post-menarche: same as adult dosing (one tablet daily for 21 days) after evaluating individual risk factors.
Not indicated for use in postmenopausal women. No specific considerations available.
Not indicated for use in postmenopausal women due to increased risk of thrombotic events and lack of benefit.
Cigarette smoking increases risk of serious cardiovascular events from combination oral contraceptives (COCs). Women over 35 who smoke should not use COCs.
Cigarette smoking increases the risk of serious cardiovascular events from combination oral contraceptive use. This risk increases with age, especially in women over 35, and with the number of cigarettes smoked. Women who use combination hormonal contraceptives should be strongly advised not to smoke.
["Thrombotic disorders (e.g., thrombophlebitis, pulmonary embolism, stroke, myocardial infarction)","Hepatic disease (including hepatic adenoma or carcinoma)","Hypertension","Gallbladder disease","Carbohydrate/lipid metabolism disturbances","Headache (including migraine with focal symptoms)","Uterine bleeding irregularities"]
["Increased risk of thromboembolic disorders (e.g., DVT, PE) and cardiovascular events (MI, stroke).","Elevated blood pressure.","Increased risk of gallbladder disease.","Hepatic adenoma or hepatocellular carcinoma.","Glucose intolerance and adverse effects on lipid metabolism.","Chloasma (melasma) exacerbated by UV exposure.","Retinal thrombosis or other ocular effects.","Menstrual irregularities and amenorrhea.","Cervical cancer risk (HPV-related)."]
["Known or suspected pregnancy","Current or history of thromboembolic disorders (e.g., DVT, PE)","Cerebrovascular or coronary artery disease","Known or suspected breast cancer or other estrogen-sensitive neoplasia","Undiagnosed abnormal genital bleeding","Hepatic adenoma or carcinoma, or active liver disease","Hypersensitivity to any component","Smoking in women over 35 years","Uncontrolled hypertension","Diabetes with vascular involvement","Migraine with aura if >35 years","Major surgery with prolonged immobilization"]
["Known or suspected pregnancy.","Current or history of thrombophlebitis or thromboembolic disorders.","History of DVT or PE.","Cerebrovascular or coronary artery disease.","Known or suspected breast carcinoma or estrogen-dependent neoplasia.","Undiagnosed abnormal genital bleeding.","Cholestatic jaundice of pregnancy or jaundice with prior OC use.","Hepatic adenoma or carcinoma.","Known hypersensitivity to any component."]
Data Pending Review
Data Pending Review
No specific food restrictions; however, grapefruit juice may increase estrogen levels (minor interaction). Avoid St. John's wort, which can reduce contraceptive efficacy.
No significant food interactions. However, grapefruit juice may increase estrogen levels, but clinically negligible. Avoid excessive alcohol as it may worsen liver metabolism.
First trimester: Risk of congenital anomalies (limb defects, neural tube defects) based on case reports; overall risk low. Second/third trimester: Possible increased risk of intrauterine growth restriction and preterm birth. Postnatal: Potential for jaundice and transient hormonal effects in neonates.
First trimester: Mestranol and norethindrone are associated with a slightly increased risk of congenital anomalies, particularly cardiovascular defects and limb reduction defects, although absolute risk is low. Second and third trimesters: Continued exposure may lead to fetal adrenal suppression, liver impairment, and pseudointersexuality in female fetuses due to androgenic effects of norethindrone. Overall, contraceptive use during pregnancy is contraindicated.
Contraindicated in breastfeeding due to estrogens reducing milk production and quality. Limited data; M/P ratio not established. Alternative methods preferred.
Excreted in breast milk in small amounts; M/P ratio not established. May reduce milk production and quality, especially with high-dose estrogens. Use during lactation is generally not recommended, particularly in early postpartum. Consider non-hormonal contraception.
No dose adjustments needed as drug is contraindicated during pregnancy. Discontinue immediately upon confirmed pregnancy; pharmacokinetic changes not applicable.
Contraindicated during pregnancy; no dose adjustments apply as it should be discontinued immediately if pregnancy occurs.
Category C
Category C
ORTHO TRI-CYCLEN 21 contains norgestimate and ethinyl estradiol; it is a triphasic oral contraceptive with varying hormone doses across 21 active pills. Its progestin component has low androgenicity, making it suitable for patients with acne or hirsutism. Monitor for thromboembolic risk, especially in smokers over 35. Missed pill management: if one active pill is missed, take it as soon as remembered and continue; if two or more are missed, use backup contraception and consider emergency contraception.
ORTHO-NOVUM 1/50 21 is a combination oral contraceptive containing 1 mg norethindrone and 50 mcg mestranol. It has higher estrogen content than modern pills, increasing thromboembolic risk. Counsel patients to avoid smoking, especially over age 35. Use as directed for 21 days on, 7 days off. Missed pills require backup contraception.
Take one pill daily at the same time for 21 days, then 7 placebo pills.Use backup contraception (e.g., condoms) for the first 7 days of initial use.Common side effects: nausea, breast tenderness, breakthrough bleeding; these often improve after 2-3 cycles.Report signs of blood clots: leg pain/swelling, chest pain, sudden shortness of breath, severe headache.Smoking increases blood clot risk; do not smoke while using this medication.If severe vomiting or diarrhea occurs within 4 hours after taking a pill, consider it missed and follow missed pill instructions.
Take one pill daily at the same time for 21 consecutive days, then none for 7 days.If you miss a pill, take it as soon as remembered; if more than 24 hours late, use backup contraception for 7 days.Do not smoke while taking this medication, especially if over 35, due to increased risk of blood clots.Common side effects include nausea, breast tenderness, and breakthrough bleeding, especially in the first few months.This pill does not protect against HIV or other sexually transmitted infections.