Ethosuximide
Ethosuximide. T-type Ca²⁺ channel blocker in thalamocortical circuits — first-line for absence seizures (childhood). Doesn't treat tonic-clonic… Oral half-life 2.2 d.
T-type Ca²⁺ channel blocker in thalamocortical circuits — first-line for absence seizures (childhood). Doesn't treat tonic-clonic; specifically fits the spike-and-wave thalamic mechanism of absence epilepsy.
PK: THE CONTROL OF THIS BATCH, AND IT PASSES EVERY TEST. The volume is verbatim AND IS CORRECTLY THE CONTROL ARM — the patient arm in that study is the enzyme-induced one — so the range-interior class is acquitted rather than merely absent. Class 6 is acquitted BY CONSTRUCTION: an apparent volume paired with a bioavailability pinned at unity divides by absorption exactly once. And the clearance test passes handsomely against the paper own verbatim figure, corroborated independently to one percent by a second volunteer study. The half-life was the only soft spot, sitting near the midpoint of two healthy-volunteer studies where its own citation states "53.7 +/- 14.3" for controls; moving to the verbatim value IMPROVES the clearance agreement and is cosmetic otherwise. The absorption rate is unsourced BUT ACQUITTED ON SHAPE: it implies a peak at 3.33 h, which is not round, not a half-hour boundary, not a range endpoint, and sits inside the published band.
Pharmacokinetics
- Oral — t½ 2.2 d · F 100% · ka 8.697 h⁻¹ · Vd 49 L
Sources: PMID:8799524, PMID:36537292