Description ergoloid mesylate is a dihydrogenated ergot (claviceps purpurea) derivative alkaloid used as a vasodilator agent.indication for use as an adjunct therapy for patients with dementia.mechanism of action ergoloid mesylates act centrally, decreasing vascular tone and slowing the heart rate, and acts peripherally to block alpha-receptors. one other possible mechanism is the effect of ergoloid mesylates on neuronal cell metabolism, resulting in improved oxygen uptake and cerebral metabolism, thereby normalizing depressed neurotransmitter levels.