- the immediate precursor in the synthesis of NE - important in sodium excretion and renal function - an important neurotransmitter in the central nervous system and involved in the reward stimulus relevant to addiction - Deficiency in ganglia: PARKINSON'S DISEASE (Levodopa) - INCREASED level: Psychosis - DOC for CARDIOGENIC and SEPTIC SHOCK - SUPERIOR than NE because of increased blood flow in the kidneys - Used to treat HYPOTENSION and SEVERE HEAR FAILURE