This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hypeension, Arrhythmias, Dyslipidemia, Subject name: Pharmacology
Which of the following drug is not a blocker of L-type of calcium channels? 
Select and explain. 
A. Dilitiazem, B. Amlodipine, C. Ethosuximide, D. Verapamil
C: Ethosuximide
Answer: C: Ethosuximide 
Explanation: L type Ca2+ channels present in CVS T type Ca2+ channels present in CNS Ethosuximide is a blocker of T type of calcium channels and is used for treatment of absence seizures. 3 groups of L-type CCB: Phenylalkylamines Benzothiazepines Dihydropyridines Verapamil Diltiazem Nifedipine Nicardipine Nimodipine Amlodipine Nimodipine: Cerebro-selective CCB Clinidipine: Blocks both L- Ca2+ and T- Ca2+.