Imipramine, a tricyclic antidepressant, acts as a potent inhibitor of serotonin and norepinephrine reuptake, which modulates pain perception and neurotransmitter signaling in the central nervous system. While not a first-line treatment for cluster headaches, it may help reduce headache frequency and intensity by altering neural pain pathways and potentially influencing neurovascular mechanisms associated with cluster headache pathogenesis.