Sodium channel blockers are a class of medications that inhibit the flow of sodium ions through specific channels in cell membranes. By blocking these channels, they can help stabilize electrical activity in the heart and nervous system, making them useful in treating conditions like arrhythmias and epilepsy. These drugs work by preventing the rapid depolarization of neurons and cardiac cells, which is essential for transmitting electrical signals. Common examples of sodium channel blockers include lidocaine and carbamazepine, which are used to manage pain and control seizures, respectively.