The complete mechanism of Duralast pill is yet unknown. However, researchers presume that Duralast works to halt the transportation of serotonin, a common neurotransmitter. This medication enhances the action of serotonin brain chemicals and controls the excitement. It results in controlling early ejaculation. Dapoxetine is an SSRI, it was initially approved to treat depression, but it was found that several men experienced delayed ejaculation.