Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) is indicated for the prevention of pregnancy in women who elect to use oral contraceptives as a method of contraception.

Oral contraceptives are highly effective. Table 2 lists the typical unplanned pregnancy rates for users of combination oral contraceptives and other methods of contraception. The efficacy of these contraceptive methods, except sterilization, the IUD, and the Norplant® system, depends upon the reliability with which they are used. Correct and consistent use of methods can result in lower failure rates.

TABLE 2: Percentage of women experiencing an unintended pregnancy during the first year of typical use and the first year of perfect use of contraception and the percentage continuing use at the end of the first year. United States.

To achieve maximum contraceptive effectiveness, Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) should be taken exactly as directed and at intervals not exceeding 24 hours. Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) tablets may be administered without regard to meals.

Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) provides a regimen consisting of 24 white active tablets of Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) and 4 brown non-hormonal (placebo) tablets of ferrous fumarate. The ferrous fumarate tablets do not serve any therapeutic purpose.

During the first cycle of use

The possibility of ovulation and conception prior to initiation of medication should be considered. The patient is instructed to begin taking Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) on either Day 1 of menstruation (Day 1 Start) or the first Sunday after the onset of menstruation (Sunday Start). If menstruation begins on a Sunday, the first tablet (white) is taken that day. One white tablet should be taken daily for 24 consecutive days followed by one brown tablet daily for 4 consecutive days. Withdrawal bleeding should usually occur within three days following discontinuation of white tablets and may not have finished before the next pack is started. During the first cycle with a Sunday start, contraceptive reliance should not be placed on Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) until a white tablet has been taken daily for 7 consecutive days and a non-hormonal back-up method of birth control (such as condoms or spermicide) should be used during those 7 days.

The patient begins her next and all subsequent 28-day courses of tablets on the same day of the week on which she began her first course, following the same schedule: 24 days on white tablets-4 days on brown tablets. If in any cycle the patient starts tablets later than the proper day, she should protect herself against pregnancy by using a non-hormonal back-up method of birth control until she has taken a white tablet daily for 7 consecutive days.

Switching from another hormonal method of contraception

When the patient is switching to Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) after completing a 21-day regimen of oral contraceptive tablets, transdermal patches, or a vaginal ring, she should wait 7 days after her last tablet, patch, or ring before she starts Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) . She will probably experience withdrawal bleeding during that week. She should be sure that no more than 7 days pass after her previous 21-day regimen. When the patient is switching to Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) after completing a 28-day regimen of oral contraceptive tablets, she should start her first pack of Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) on the day after her last tablet. She should not wait any days between packs. The patient may switch any day from a progestin-only pill and should begin Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) the next day. If switching from an implant or injection, the patient should start Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) on the day of implant removal or, if using an injection, the day the next injection would be due.

If spotting or breakthrough bleeding occurs

The patient is instructed to continue on the same regimen. This type of bleeding is usually transient and without significance; however, if the bleeding is persistent or prolonged, the patient is advised to consult her healthcare provider. Although pregnancy is unlikely if Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) is taken according to directions, if withdrawal bleeding does not occur, the possibility of pregnancy must be considered. If the patient has not adhered to the prescribed schedule (missed one or more tablets or started taking them on a day later than she should have), the probability of pregnancy should be considered at the time of the first missed period and appropriate diagnostic measures taken. If the patient has adhered to the prescribed regimen and misses two consecutive periods, pregnancy should be ruled out. Hormonal contraceptives should be discontinued if pregnancy is confirmed.

For additional patient instructions regarding missed pills

See the "WHAT TO DO IF YOU MISS PILLS" section in the DETAILED PATIENT LABELING. Any time the patient misses two or more white tablets, she should also use another method of non-hormonal back-up contraception until she has taken a white tablet daily for seven consecutive days. If the patient misses one or more brown tablets, she is still protected against pregnancy provided she begins taking the active white tablets again on the proper day. If breakthrough bleeding occurs following missed white tablets, it will usually be transient and of no consequence. The possibility of ovulation increases with each successive day that scheduled white tablets are missed. Therefore, the risk of pregnancy increases with each active (white) tablet missed.

Use after pregnancy, abortion or miscarriage

Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) should be initiated no earlier than 28 days postpartum in the nonlactating mother due to the increased risk for thromboembolism. When the tablets are administered in the postpartum period, the increased risk of thromboembolic disease associated with the postpartum period must be considered (see CONTRAINDICATIONS, WARNINGS, and PRECAUTIONS concerning thromboembolic disease). The patient should be advised to use a non-hormonal back-up method for the first 7 days of tablet taking. However, if intercourse has already occurred, the possibility of ovulation and conception prior to initiation of medication should be considered.

Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) may be initiated after a first-trimester abortion or miscarriage; if the patient starts Loestrin 24 Fe (norethindrone acetate and ethinyl estradiol) immediately, additional contraceptive measures are not needed.

For additional patient instructions regarding complete dosing instructions, see the "HOW TO TAKE THE PILL" section in the DETAILED PATIENT LABELING.

Loestrin® 24 Fe (norethindrone acetate and ethinyl estradiol) is available in blister cards (dispensers) containing 24 white active tablets and 4 brown placebo tablets. Each white, round tablet contains 1 mg of norethindrone acetate and 20 mcg of ethinyl estradiol and is imprinted with WC on one side and 530 on the other. Each brown, round tablet contains 75 mg ferrous fumarate.

N 0430-0530-14 Cartons of 5 blister cards (dispensers)

Keep this drug and all drugs out of the reach of children.

Store at 25° C (77° F); excursions permitted to 15 - 30° C (59 - 86° F) [see USP Controlled Room Temperature].

References are available upon request.

Manufactured by: Warner Chilcott Company, Inc. Fajardo, PR 00738. Marketed by: Warner Chilcott (US), LLC Rockaway, NJ 07866. 1-800-521-8813. Revised July 2008. FDA Rev date: 4/29/2003

Last reviewed on RxList: 9/18/2008
This monograph has been modified to include the generic and brand name in many instances.