Comparative Pharmacology
Head-to-head clinical analysis: QUARTETTE versus TRI NORINYL 28 DAY.
Peer-Reviewed Evidence
Head-to-head clinical analysis: QUARTETTE versus TRI NORINYL 28 DAY.
QUARTETTE vs TRI-NORINYL 28-DAY
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing drospirenone, ethinyl estradiol, levomefolate calcium, and metformin. Drospirenone is a progestin with antimineralocorticoid and antiandrogenic activity. Ethinyl estradiol is an estrogen. Levomefolate calcium is a folate supplement. Metformin is a biguanide that decreases hepatic glucose production and improves insulin sensitivity.
Combination oral contraceptive containing ethinyl estradiol and norethindrone. Suppresses gonadotropin (FSH and LH) release via negative feedback, inhibiting ovulation. Also increases viscosity of cervical mucus and alters endometrial lining to reduce implantation likelihood.
3 mg orally once daily for 21 days followed by 7 days of placebo.
One tablet orally once daily for 21 days, followed by one placebo tablet orally once daily for 7 days. Each active tablet contains 0.035 mg ethinyl estradiol and 0.5 mg norethindrone (7 days), 0.035 mg ethinyl estradiol and 1.0 mg norethindrone (9 days), and 0.035 mg ethinyl estradiol and 0.5 mg norethindrone (5 days).
None Documented
None Documented
Terminal elimination half-life is 12-14 hours; clinically this supports once-daily dosing with steady state achieved within 2-3 days.
Ethinyl estradiol: 17 ± 6 hours (terminal); Norethindrone: 10 ± 3 hours (terminal). Steady-state achieved after 7-14 days.
Renal excretion accounts for 55% (primarily as unchanged drug), biliary/fecal excretion 35%, and the remainder undergoes metabolic clearance.
Renal: 40% as metabolites; Fecal: 50% as metabolites; Biliary: minor; unchanged ethinyl estradiol excreted in urine <5%, norethindrone <1%.
Category C
Category C
Oral Contraceptive
Oral Contraceptive