From the Guidelines
Levonorgestrel is the recommended emergency contraception within 24 hours due to its efficacy and lack of interaction with fluconazole, making it a safer choice compared to ulipristal acetate. When considering emergency contraception within 24 hours, it's essential to weigh the efficacy of different options. According to the most recent guidelines 1, levonorgestrel reduces pregnancy risk by about 85% when taken within 24 hours, while ulipristal acetate (ella) is approximately 95% effective in the same timeframe. However, the interaction between fluconazole and ulipristal acetate, which can increase the latter's blood levels and potentially cause more side effects, makes levonorgestrel a preferable option in this context.
Key points to consider:
- The efficacy of emergency contraception decreases with time, so it's crucial to take the pill as soon as possible after unprotected sex.
- Levonorgestrel is available in a single 1.5mg tablet, which is the standard dose for emergency contraception.
- Side effects of levonorgestrel may include nausea, headache, fatigue, and irregular bleeding.
- It's essential to remember that emergency contraception does not protect against sexually transmitted infections and is not as reliable as regular contraceptive methods for ongoing pregnancy prevention.
In terms of potential interactions, fluconazole can increase the blood levels of ulipristal acetate, potentially causing more side effects 1. In contrast, levonorgestrel does not have this interaction, making it a safer choice for individuals taking fluconazole. The most recent guidelines from 2024 1 support the use of levonorgestrel as an effective emergency contraception option, especially when considering potential interactions with other medications.
From the Research
Efficacy of Levonorgestrel and Ulipristal Acetate
- Levonorgestrel is effective for emergency contraception when taken within 72 hours of unprotected intercourse, with a single dose of 1.5 mg or two doses of 0.75 mg taken 12-24 hours apart 2, 3.
- Ulipristal acetate is considered the most effective oral option for emergency contraception, with a higher efficacy rate compared to levonorgestrel 4, 5, 6.
- The efficacy of levonorgestrel and ulipristal acetate within 24 hours is not directly compared in the provided studies, but both are effective when taken promptly after unprotected intercourse.
Potential Interactions with Fluconazole
- There is no mention of potential interactions between fluconazole and levonorgestrel or ulipristal acetate in the provided studies.
- However, it is known that certain medications can interact with emergency contraceptives, and fluconazole may potentially affect the efficacy of these medications, although this is not specified in the provided evidence.
Comparison of Levonorgestrel and Ulipristal Acetate
- Ulipristal acetate is considered more effective than levonorgestrel, with a higher efficacy rate in preventing pregnancy 4, 5, 6.
- Levonorgestrel is available over-the-counter, while ulipristal acetate requires a prescription 4, 6.
- Both levonorgestrel and ulipristal acetate are safe and effective options for emergency contraception, with minimal side effects 4, 3, 5, 6.