Dopamine is a neuromodulator that controls the likelihood that certain brain areas will be active and other brain areas won't be active. It is associated with motivation, craving, and movement. Dopamine is released from several places in the brain, including the mesolimbic reward pathway, which is a whole set of places in the brain or circuits designed to get us motivated and craving and in pursuit of things. Sugar or sweet tastes have an incredibly potent ability to activate dopamine release within the mesolimbic reward pathway, which then are conveyed to pathways for motor behavior, and in general, place us into modes of focused action toward getting more of whatever was sweet. Dopamine can change the way that our neural circuits work at a local scale and at a very broad scale. Many drugs and supplements that increase dopamine will actually make it harder for you to sustain dopamine release over long periods of time and achieve those peaks that most of us are craving when we are in pursuit of things.
This is not medical advice. Consult your physician before changing protocols.