Anti-seizure Medication Tapering Post-Pregnancy

Guidance on Tapering ASMs after Pregnancy

Most anti-seizure medications (ASMs) may require higher doses during pregnancy due to changes in drug clearance. However, patients should reduce these increased doses in the first few weeks after giving birth to prevent potential toxicity.

It’s important for clinicians to develop a postpartum tapering plan for patients on ASMs. Share the plan with the patient and their obstetrician a few weeks before the expected delivery date. Waiting until after delivery is not advisable and risks toxicity in some cases. However, if the taper plan is not in place prior to delivery, there is no need for concern from clinician or patient, as the first dosage decrease is not until more than 48 hours after delivery. 

The postpartum tapering plan may involve maintaining the patient at a slightly higher dose than pre-pregnancy levels. The higher dose can protect the patient from the effects of sleep deprivation and added stressors during the postpartum period.

Topics covered on this page include:

• Tapering Considerations for Specific Medications
• Lamotrigine Tapering Example
• Oxcarbazepine
• Levetiracetam
• In Case of Miscarriage or Abortion

Tapering Considerations for Specific Medications

For most ASMs, the initial step is to hold at the delivery dose for 48 hours. After this period, a gradual tapering process should be implemented over the appropriate interval for the specific ASM, typically lasting three weeks. 

Without changes in dosage, lamotrigine levels will increase within the first few days following delivery and will continue to increase over the three weeks postpartum. Decreasing dosage adjustments should be made over this time frame. Similarly, levetiracetam can be reduced to near prepartum levels within two to three weeks after delivery. Other ASMs that are primarily renally cleared, such as zonisamide and lacosamide, can also be tapered over approximately three weeks. Eslicarbazepine, gabapentin, lacosamide, oxcarbazepine, pregabalin, rufinamide, topiramate, valproic acid, and vigabatrin should also be returned to near baseline over the first three weeks postpartum. 

For ASMs that induce P450 enzymes, such as carbamazepine, clobazam, phenytoin, and others, a slower tapering period of six weeks is recommended due to limited evidence that suggests otherwise.

Lamotrigine Example: 

On postpartum day two (the day after delivery being day one), reduce the dose by 100 mg, and then continue decreasing the dosage every three to five days. The speed of dose reduction should be based on the patient's required ASM level. For example, a patient needing a level of 10 mcg/mL is at higher risk of postpartum toxicity and may require a faster empiric titration compared to those maintaining levels of 3-5 mcg/mL. 

A typical goal for lamotrigine titration is to reach the postpartum dose plus 50 mg/day within 3 weeks, by reducing in similar increments every three to four days. The dosage amount that will need to be reduced can be represented as:

Postpartum dose - Prepartum dose + 50 mg by week 3 (reducing q 3-4 d)

It is essential to note that cutting extended-release pills in half is generally not recommended except for very short-term use as a backup plan. Additionally, if a patient is on extended-release pills, some of the dose can be given using immediate-release pills to help accommodate all of the different dosing combinations. Clinicians should educate patients about signs of toxicity, which include vertigo, vomiting, blurry/double vision, and ataxia. If a patient experiences any of these signs, they should contact their healthcare provider immediately. 

Ideally, an in-person or telehealth visit should occur at week 2 postpartum to check if the patient is following the reduction plan and assess progress, side effects, seizures, sleep, and mood. Patients should then be seen at six weeks postpartum to check levels. 

Postpartum Tapering Example: Patient with focal epilepsy on Lamotrigine

• Prepartum dose: 100 mg-100 mg (level 4 mcg/ml)
• End-of-pregnancy dose: 300 mg-300 mg

Wait at least one week after the last change to check levels, either at this point or at 6 weeks postpartum. (See the Anti-seizure Medication Tapering Schedule Tool.)

For Oxcarbazepine:

Medications like lamotrigine and oxcarbazepine follow similar protocols. However, the first dose decrease for oxcarbazepine will more commonly be 150 mg or 300 mg. 

It is essential to note that cutting extended-release pills in half is generally not recommended except for very short-term use as a backup plan. Some of the dose can be given using immediate-release pills to help accommodate all of the different dosing combinations. Clinicians should educate patients about signs of toxicity, which include vertigo, vomiting, blurry/double vision, and ataxia. If patients experience any of these signs, they should contact their healthcare provider right away. 

Patients should be seen at six weeks postpartum for level checks. Ideally, a telehealth or in-person visit should occur at Week Two to assess progress, side effects, seizures, sleep, and mood if the individual is following the dose reduction plan. 

For Levetiracetam: 

When tapering levetiracetam, the goal is to achieve the desired dosage by subtracting the prepartum dose from the postpartum dose and adding 500 mg within three weeks. This tapering process involves reducing the dosage 2, 7, 14, and 21 days after delivery by the following amount:

Postpartum dose - Prepartum dose + 500 mg by week 3 (reducing q 7 d)

The clinician should monitor levetiracetam levels at six weeks postpartum and attempt to obtain the levels at the same interval post-dose as in the patient's previous history. Clinicians should be cautious when interpreting levetiracetam levels, as the amount of hours post-dose creates a lot of variation in the levetiracetam blood level. 

Postpartum Tapering Example: Patient with generalized epilepsy on levetiracetam

• Prepartum dose: 750 mg-750 mg (level 15 mcg/ml)
• End of pregnancy dose: 2000 mg-2000 mg

Check levels at six weeks postpartum. (See the Anti-seizure Medication Tapering Schedule Tool.)

Clinicians should closely monitor their patient's response to tapering and adjust the dosage as needed to ensure appropriate seizure control and avoid potential complications. 

In Case of Miscarriage or Abortion

If a patient miscarriages or has an abortion, seizure medication doses will need to be adjusted if they have been increased. This is usually done over 2-8 weeks after the end of a pregnancy. You want to be back on the lowest dose you need before trying to conceive again. 

Guide Your Patients

Information about the different ASMs, level recommendations, and tapering methods can be highly technical and confusing for people unfamiliar with medical terminology. It’s important for clinicians to work with their patients to help them understand the process and ensure that it’s done safely and effectively. 

During the postpartum visit, you should discuss long-term management, returning to pre-partum ASM dose prior to another pregnancy (if feasible), sleep and breastfeeding status, prenatal vitamins/folic acid, and contraception (which should also be discussed in the third trimester).

Reviewed by: Page Pennell, MD FAES, August 2023