Starting Norethindrone After Switching from Alesse
Yes, norethindrone (progestin-only pill) 0.35 mg can be started on the first day of withdrawal bleeding after discontinuing Alesse (levonorgestrel and ethinyl estradiol). This approach provides immediate contraceptive protection without requiring backup methods.
Rationale for Starting During Withdrawal Bleeding
- Starting norethindrone on the first day of withdrawal bleeding (after stopping combined hormonal contraceptives like Alesse) ensures continuous hormonal contraception without gaps in protection 1
- This timing takes advantage of the suppressed ovarian activity from the previous combined hormonal contraceptive while transitioning to the progestin-only method 1
- Beginning on the first day of withdrawal bleeding helps maintain endometrial stability and reduces the risk of irregular bleeding, which is a common side effect with progestin-only pills 1
Norethindrone Administration Guidelines
- Take norethindrone 0.35 mg at the same time every day without breaks or pill-free intervals 1
- Unlike combined hormonal contraceptives, progestin-only pills must be taken within a strict 3-hour window each day to maintain contraceptive efficacy 2
- Continuous daily administration is essential as progestin-only pills have a shorter half-life compared to combined hormonal contraceptives 1
Potential Side Effects When Switching
- Increased likelihood of irregular bleeding patterns when transitioning from a combined hormonal contraceptive to a progestin-only pill 2
- Up to 54.5% of adolescents may experience irregular bleeding with norethindrone 0.35 mg, which is the most common reason for discontinuation 2
- Other possible side effects include headaches, mood changes, and breast tenderness, though these are generally mild to moderate in severity 3
Important Considerations and Precautions
- Norethindrone is contraindicated in patients with pregnancy, history of thromboembolism, undiagnosed vaginal bleeding, active liver disease, breast cancer or hormone-sensitive cancers, and uncontrolled hypertension 4
- Progestin-only pills like norethindrone may have less impact on cardiovascular risk factors compared to combined hormonal contraceptives, making them suitable for women with certain cardiovascular risk factors 1
- Unlike combined hormonal contraceptives, norethindrone 0.35 mg does not contain estrogen, which eliminates estrogen-related side effects and risks 1
Clinical Pearls
- If withdrawal bleeding does not occur after stopping Alesse, consider performing a pregnancy test before starting norethindrone 1
- Advise patients that the bleeding pattern with norethindrone may differ significantly from their experience with Alesse, with potential for more frequent spotting or irregular bleeding 2
- For patients concerned about irregular bleeding, counseling about this expected side effect before initiating therapy may improve adherence 2