What birth control methods are suitable for patients with epilepsy?

Birth Control Options for Patients with Epilepsy

For patients with epilepsy, intrauterine devices (IUDs) are the most appropriate contraceptive choice, particularly the copper IUD which has no drug interactions with antiepileptic medications and provides highly effective contraception. 1

Understanding the Interaction Between Antiepileptic Drugs and Contraceptives

The selection of contraception for women with epilepsy requires careful consideration of potential drug interactions between antiepileptic drugs (AEDs) and hormonal contraceptives:

Enzyme-Inducing AEDs

• Problematic AEDs: Phenytoin, carbamazepine, barbiturates, primidone, topiramate, and oxcarbazepine 1
• Effect: These AEDs induce liver enzymes that accelerate the metabolism of hormonal contraceptives, potentially reducing their effectiveness
• Classification: Category 3 (risks usually outweigh benefits) for combined hormonal contraceptives and progestin-only pills 1

Non-Enzyme-Inducing AEDs

• Examples: Valproic acid, gabapentin, levetiracetam, zonisamide
• Effect: No significant interaction with hormonal contraceptives
• Classification: Category 1 (no restriction for use) 1

Special Case - Lamotrigine

• Unique interaction: Combined hormonal contraceptives can decrease lamotrigine levels, potentially increasing seizure risk 1
• Classification: Category 3 for combined hormonal contraceptives when lamotrigine is used as monotherapy 1

Recommended Contraceptive Options

First-Line Options:

1. Copper IUD (Paragard)

   • Recommendation level: Category 1 (no restrictions) for all women with epilepsy 1
   • Advantages: No hormonal interactions, highly effective (>99%), long-acting (up to 10 years)
   • No drug interactions with any AEDs 1

2. Levonorgestrel IUD (Mirena, Kyleena, etc.)

   • Recommendation level: Category 1 for all women with epilepsy 1
   • Advantages: Minimal systemic hormone absorption, highly effective (>99%), reduces menstrual bleeding
   • No significant interactions with AEDs due to primarily local hormone action 1

Second-Line Options:

1. Depot Medroxyprogesterone Acetate (DMPA) Injection

   • Recommendation level: Category 1 with most AEDs; Category 2 with enzyme-inducing AEDs 1
   • Consideration: For women on enzyme-inducing AEDs, consider administering every 10 weeks instead of 12 weeks 2
   • Caution: Potential concerns about bone mineral density with long-term use

2. Contraceptive Implant (Nexplanon)

   • Recommendation level: Category 2 with enzyme-inducing AEDs 1
   • Caution: Reduced efficacy possible with enzyme-inducing AEDs 2

Options to Use with Caution:

1. Combined Hormonal Contraceptives (pills, patch, ring)

   • Recommendation level: Category 3 with enzyme-inducing AEDs 1
   • If used: Choose preparations with at least 50 μg ethinyl estradiol 1
   • Additional protection: Consider backup barrier method
   • Avoid in women taking lamotrigine monotherapy due to risk of decreased lamotrigine levels 1

2. Progestin-Only Pills

   • Recommendation level: Category 3 with enzyme-inducing AEDs 1
   • Concern: High failure rates when used with enzyme-inducing AEDs 2

Clinical Approach Algorithm

1. Identify the specific AED regimen:

   • Determine if patient is taking enzyme-inducing AEDs
   • Check for lamotrigine monotherapy

2. Assess pregnancy risk factors:

   • Epilepsy is listed as a condition where unintended pregnancy poses increased health risks 1
   • Prioritize highly effective contraception methods

3. Recommend appropriate contraception:

   • For all women with epilepsy: IUDs (copper or hormonal) as first choice
   • For women on enzyme-inducing AEDs: Avoid combined hormonal contraceptives and progestin-only pills
   • For women on lamotrigine monotherapy: Avoid combined hormonal contraceptives

4. Provide counseling about:

   • Effectiveness rates
   • Potential for breakthrough bleeding as a sign of contraceptive failure
   • Need for backup methods with certain combinations

Important Clinical Considerations

• Counseling impact: Studies show that specific contraceptive counseling by neurologists significantly increases the likelihood of women with epilepsy choosing appropriate methods like IUDs 3

• Reproductive disorders: Women with epilepsy have higher rates of reproductive endocrine disorders, making effective contraception particularly important 1

• Seizure control: Unplanned pregnancy may lead to medication changes that could affect seizure control, making highly effective contraception crucial for maintaining quality of life and reducing morbidity 1

• Common pitfall: Assuming that absence of breakthrough bleeding means hormonal contraception is effective in women taking enzyme-inducing AEDs - additional protection is still recommended 4