From the Guidelines
Progestin-only birth control pills, such as Micronor, Camila, or Norethindrone, are the recommended choice for women taking lamotrigine due to their minimal interaction with this anticonvulsant medication. According to the most recent guidelines 1, progestin-only pills (POP) are classified as a category 1 for women using lamotrigine, indicating no restrictions for use. This is in contrast to combined hormonal contraceptives (CHC), which are classified as category 3, suggesting that the benefits of using CHC may be outweighed by the risks, particularly the potential for reduced lamotrigine effectiveness due to increased metabolism induced by estrogen components.
The key consideration here is the effect of estrogen on lamotrigine levels. Estrogen can induce liver enzymes that accelerate lamotrigine metabolism, potentially lowering its blood levels by up to 50% and compromising seizure control 1. Progestin-only pills do not contain estrogen, thus they do not significantly affect lamotrigine metabolism. However, it is still crucial to monitor lamotrigine levels periodically, especially when initiating or discontinuing contraceptive use, as minor fluctuations in lamotrigine levels may occur.
Some important points to consider:
- Progestin-only pills should be taken consistently at the same time every day to maximize their effectiveness.
- Non-hormonal contraceptive methods, such as copper IUDs or barrier methods, are also viable alternatives that do not interact with lamotrigine.
- It is essential for women to discuss their contraceptive options with both their neurologist and gynecologist to ensure that their seizure control remains stable while providing effective birth control.
In summary, for women taking lamotrigine, progestin-only birth control pills are the preferred choice due to their minimal impact on lamotrigine levels, thereby reducing the risk of compromised seizure control.
From the Research
Birth Control Options with Lamotrigine
To find a birth control pill that does not interact with lamotrigine, an anticonvulsant medication, we need to consider the types of birth control that are less likely to interact with this medication.
- Combined Oral Contraceptives: According to 2, combined oral contraceptives can reduce lamotrigine plasma levels by more than 50%. This suggests that combined oral contraceptives may not be the best option for women taking lamotrigine.
- Progesterone-Only Pill: The study 3 suggests that there are no interactions between the progesterone-only pill and lamotrigine. This makes the progesterone-only pill a potential option for women taking lamotrigine.
- Levonorgestrel Implants: Although 3 mentions that levonorgestrel implants are contraindicated in women receiving certain antiepileptic drugs, it does not specifically mention lamotrigine as one of these drugs. However, another study 4 found that a progestin-containing intrauterine device (IUD) is a safe and acceptable long-acting contraceptive for women with epilepsy, including those taking lamotrigine.
- Medroxyprogesterone Injections: The study 3 recommends that medroxyprogesterone injections be given every 10 weeks to women who are receiving antiepileptic drugs that induce hepatic microsomal enzymes. However, since lamotrigine is not one of these drugs, the normal dosing schedule may be used.
Key Findings
- Lamotrigine does not interact with the progesterone-only pill, medroxyprogesterone injections, or levonorgestrel implants, according to 3 and 4.
- Combined oral contraceptives can reduce lamotrigine plasma levels, as found in 2.
- Gabapentin, another anticonvulsant, does not interact with a contraceptive regimen of norethindrone acetate and ethinyl estradiol, as shown in 5. However, this does not directly relate to lamotrigine.
It is essential to consult a healthcare provider to determine the best birth control option for women taking lamotrigine, as individual circumstances may vary.