Dopamine is a catecholamine neurotransmitter abundant in the brain, which is an endogenous nitrogenous organic compound, and is an intermediate product of tyrosine (an aromatic amino acid) produced by dihydroxyphenylalanine in the metabolic process. It can regulate a variety of physiological activities in the brain. After the human cerebral cortex issues commands, the brain signals are transmitted down through the electrical activity of neurons, and between two neurons, the brain signals are transmitted as neurotransmitters. There are various types of neurotransmitters and catecholamines belong to one of them, dopamine is a type of catecholamine that transmits excitatory messages. Dopamine plays an important role in motor control, has been linked to drug addiction, and plays a very important role in memory, brain aging and mood. In the case of dopamine pathway disorders, it can cause significant psychiatric symptoms in people, such as Parkinson’s disease, schizophrenia, pituitary tumors, and Attention Deficit Hyperactivity Syndrome, to name a few. In addition to this, dopamine can also be used as a drug to treat conditions such as shock.