The present invention provides a method for treating a disease or condition in a mammal which comprises the steps of administering a therapeutically effective amount of a T type calcium channel inhibitor to effectively slow or stop progression of eukaryotic cells through the S, G2 and M phases of the cell cycle to increase the proportion of the eukaryotic cells in the G1 phase, stopping administration of the T type calcium channel inhibitor for a period of time, and administering a dosage selected from the group consisting of a dosage of at least one chemotherapeutic agent, a dosage of radiation, and combinations thereof, to kill the proportion of eukaryotic cells progressing past the G1 phase of the cell cycle after the stopping of the administration of the T type calcium channel inhibitor.
