Pregnancy-Relates: medication adjustment question

[PSUgirl2009]

Hi there,

I'm officially 14 weeks pregnant with our first child. I am currently taking 200mg of Lamotrigine ER 2x/daily. My neuro called me with the results of my last levels saying that they came in at 3.6 (should be anywhere between 2.5 and 12 to be therapeutic). Her suggestion was to raise my medication already by 50mg 2x/daily. My goal was to reach the halfway point (20 weeks) before upping the dosage. I know that Lamotrigine is one of the safest drugs to be on while pregnant but the idea of neural tube defects still scares me. Especially of we are upping the medication this early. I can only imagine how much it will have to be increased by the 3rd trimester.

Does anyone have experience with this or advice to give me? I feel like I'm failing my baby by having to raise it this early? Did they make any adjustments to your intake of folic acid as well?

 

[Nakamova]

If the level is what it has always been, and you've remained seizure-free, then there may not be a pressing need to raise the Lamictal dose. However, if the levels have dropped from their usual number, and/or you're experiencing seizure activity, then it's a good idea to go ahead and up the level. This is because the increase of estrogen that occurs during pregnancy can cause lamotrogine levels to drop drop substantially and quickly. (These changes in levels revert back to normal after delivery and and that point you would start to lower lamotrigine to pre-pregnancy levels.) Your neuro or OB/GYN should should be checking lamotrigine levels regularly to monitor any changes.

I undertand your worry about neurl tube defects, but the risk is very low -- numbers from the N. American AED Pregnancy Registry show that women taking lamotrigine during pregnancy have about the same risk of having a baby with major birth defects as compared with women across the general population (2-3%.)

I assume you've been taking folic acid for awhile now? If your doctor thinks you are at a greater risk, your dose could be increased to the top amount (400 mcg), but needn't go any higher.