Lyleq

Generic name:norethindrone
Dosage form: tablet
Drug classes:Contraceptives, Progestins

Medically reviewed by Drugs.com. Last updated on Jan 1, 2021.

Patients should be counseled that oral contraceptives do not protect against transmission of HIV (AIDS) and other sexually transmitted diseases (STDs ) such as Chlamydia, genital herpes, genital warts, gonorrhea, hepatitis B, and syphilis.

Lyleq Description

Each light yellow to yellow LyleqTM tablet provides a continuous oral contraceptive regimen of 0.35 mg norethindrone USP daily, and the inactive ingredients include corn starch, D&C Yellow No. 10 aluminum lake, FD&C Yellow # 6 aluminum lake, lactose monohydrate, magnesium stearate, povidone and talc.

The chemical name for norethindrone is 17-Hydroxy-19-Nor-17α-pregn-4-en-20-yn-3-one. The structural formula follows:

Lyleq - Clinical Pharmacology

1. Mode of Action

Lyleq progestin-only oral contraceptives prevent conception by suppressing ovulation in approximately half of users, thickening the cervical mucus to inhibit sperm penetration, lowering the mid-cycle LH and FSH peaks, slowing the movement of the ovum through the fallopian tubes, and altering the endometrium.

2. Pharmacokinetics

Absorption

Norethindrone is rapidly absorbed with maximum plasma concentrations occurring within 1 to 2 hours after Lyleq administration (see Table 1). Norethindrone appears to be completely absorbed following oral administration; however, it is subject to first pass metabolism resulting in an absolute bioavailability of approximately 65%.

Figure 1: Mean ± SD Norethindrone Plasma Concentrations Following Lyleq Administration



Peak plasma concentrations occur approximately 1 hour after administration (mean Tmax 1.2 hours). The mean (SD) Cmax was 4816.8 (1532.6) pg/mL a