Table 2.
Antiepileptic drug clearance during pregnancy
| AED | N | Non-Pregnant
|
1st Trimester
|
2nd Trimester
|
3rd Trimester
|
|||
|---|---|---|---|---|---|---|---|---|
| Mean Clearance (SD) (range) | Mean Peak Clearance (SD) (range) | % Increasea | Mean Peak Clearance (SD) (range) | % Increasea | Mean Peak Clearance (SD) (range) | % Increasea | ||
| Monotherapy | ||||||||
| LTG | 69 | 0.87 (0.42) (0.23–2.70) | 1.64 (0.82) (0.39–4.18) | 89 | 2.53 (1.47) (0.57–9.23) | 191 | 2.09 (1.01) (0.41–5.66) | 140 |
| LEV | 15 | 1.09 (0.30) (0.68–1.63) | 2.16 (1.72) (1.10–8.15) | 98 | 3.35 (2.60) (1.18–9.51) | 207 | 2.15 (1.11) (0.71–4.32) | 97 |
| All Other Monotherapyb | 15 | 0.95 (0.64) (0.12–2.06) | 1.05 (0.82) (0.18–3.46) | 11 | 1.06 (0.72) (0.18–2.89) | 12 | 1.13 (0.81) (0.20–2.64) | 19 |
| CBZ | 6 | 1.57 (0.33) (1.21–2.06) | 1.32 (0.34) (1.00–1.88) | −16 | 1.49 (0.41) (1.09–2.26) | −5 | 1.76 (0.48) (1.29–2.54) | 12 |
| TPM | 3 | 0.59 (0.06) (0.54–0.63) | 1.58 (1.64) (0.49–3.46) | 168 | 1.36 (1.33) (0.57–2.89) | 131 | 0.65 (0.10) (0.55–0.75) | 10 |
| OXC | 2 | 0.91 (0.23) (0.74–1.07) | 1.11 (0.45) (0.79–1.42) | 22 | 2.33 (0.37) (2.07–2.59) | 156 | 2.16 (0.68) (1.68–2.64) | 137 |
| PHT | 1 | N/A | 0.52 | N/A | 0.35 | N/A | 0.40 | N/A |
| VPA | 1 | 0.15 | 0.18 | 20 | 0.18 | 20 | 0.20 | 33 |
| ZNS | 1 | 0.12 | 0.25 | 108 | 0.29 | 142 | 0.26 | 117 |
| ESM | 1 | 0.31 | 0.50 | 61 | 0.34 | 10 | 0.44 | 42 |
|
| ||||||||
| Polytherapy | ||||||||
| Allc | 33 | 1.09 (1.08) (0.18–5.19) | 2.45 (3.52) (0.23–16.79) | 125 | 2.90 (4.12) (0.26–24.26) | 166 | 1.86 (1.22) (0.35–7.02) | 71 |
| Polytherapy with LTG or LEV | 23 | 1.32 (1.19) (0.34–5.19) | 2.78 (3.74) (0.70–16.79) | 112 | 3.68 (4.71) (0.91–24.26) | 180 | 2.20 (1.23) (0.91–7.02) | 676 |
| Polytherapy without LTG or LEVd | 10 | 1.01 (0.39) (0.18–1.34) | 1.99 (2.99) (0.23–10.08) | 96 | 2.75 (0.99) (0.26–3.40) | 171 | 1.93 (0.80) (0.35–2.71) | 90 |
Compared to non-pregnant baseline.
Other AEDs used in monotherapy were carbamazepine (n=6), topiramate (n=3), oxcarbazepine (n=3), phenytoin (n=1), valproate (n=1), zonisamide (n=1), and ethosuximide (n=1). Data are separated by individual AED below.
Average of all AEDs used by each patient on polytherapy treatment. The mean number of AEDs per patient was 2.1 (range = 2–3).
These polytherapies included the following AEDs: topiramate (n=4), oxcarbazepine (n=2), valproate (n=1), phenytoin (n=1), zonisamide (n=1), and carbamazepine (n=1).
AED = antiepileptic drug; LTG = lamotrigine, LEV = levetiracetam; CBZ = carbamazepine; TPM = topiramate; OXC = oxcarbazepine; PHT = phenytoin; VPA = valproate; ZNS = zonisamide; ESM = ethosuximide; N/A = none available.