Side Effects of Ella (Ulipristal Acetate) Emergency Contraception
The most common side effects of Ella (ulipristal acetate) emergency contraception include headache (18-19%), nausea (12-13%), abdominal pain (8-15%), menstrual pain (7-13%), fatigue (6%), and dizziness (5%). 1
Common Side Effects
Ella's FDA label clearly documents the most frequently reported adverse reactions in clinical trials:
- Headache (18-19% of users)
- Nausea (12-13% of users)
- Abdominal and upper abdominal pain (8-15% of users)
- Dysmenorrhea (menstrual pain) (7-13% of users)
- Fatigue (6% of users)
- Dizziness (5% of users) 1
Menstrual Effects
Ella can affect your menstrual cycle in the following ways:
- Delayed menses: Your next period may be delayed by approximately 2-3 days after taking Ella 1
- Changes in menstrual cycle: Some women may experience their next period earlier or later than expected 1
- If your period is more than a week late after taking Ella, you should take a pregnancy test and follow up with your healthcare provider 1
Rare but Serious Side Effects
While uncommon, there are some rare but potentially serious side effects to be aware of:
- Ectopic pregnancy: If you experience severe lower abdominal pain about 3-5 weeks after taking Ella, you may have an ectopic pregnancy (pregnancy outside the womb), which requires immediate medical attention 1
Post-Marketing Reported Side Effects
The following adverse reactions have been identified during post-approval use of Ella:
- Skin reactions:
- Acne
- Hypersensitivity reactions including rash, urticaria (hives), pruritus (itching), and angioedema (swelling) 1
Special Considerations
Breastfeeding: A small amount of the hormones in Ella may pass into breast milk. Discuss with your healthcare provider about the best birth control options while breastfeeding 1
Drug interactions: Certain medications may make Ella less effective, including:
- Hormonal birth control methods (pills, implants, IUDs, patches)
- St. John's Wort
- Certain medications like bosentan, griseofulvin, phenytoin, topiramate, oxcarbazepine, carbamazepine, barbiturates, rifampin, and felbamate 1
Important Precautions After Taking Ella
Use a reliable barrier birth control method (such as condom with spermicide) until your next menstrual period 1
Do not use levonorgestrel emergency contraceptive pills within 5 days after taking Ella 1
Wait 5 days to start or resume hormonal birth control methods (such as the pill, patch, or vaginal ring) 1
If you vomit within 3 hours of taking Ella, contact your healthcare provider as you may need another dose 1
Efficacy Considerations
While not a side effect, it's worth noting that ulipristal acetate (Ella) has been shown to be more effective than levonorgestrel (Plan B) emergency contraception, especially when taken later in the 120-hour window after unprotected intercourse 2. This is particularly important for women with higher BMI, as Ella maintains better efficacy in this population compared to levonorgestrel-based emergency contraception 2.