An 8-year-old boy comes into the office with his mother due to her concern that he has not been paying attention in class or at home for the past 2 months. She states that he will often stare into space for a few seconds, even while being spoken to. Vital signs are normal, and the physical examination is unremarkable. An electroencephalogram (EEG) shows a 3-Hz spike and wave pattern. Ethosuxamide is prescribed.

Which of the following is the mechanism of action of this medication?

• A) Inhibition of calcium channels in the subthalamic nucleus
• B) Inhibition of GABA reuptake
• C) Inhibition of thalamic T-type calcium channels
• D) Inhibition of voltage gated potassium channels
• E) Inhibition of voltage gated sodium channels