Cocaine is almost two drugs in one, blending stimulant and anesthetic effects in a single molecule.
In the brain, it pumps up the volume by increasing the activity of two main neurotransmitters, norepinephrine and dopamine. At low doses, its effects include feelings of excitement and alertness, combined with decreased appetite and fatigue. Physical effects include dilated pupils, constricted blood vessels, and elevated heart rate, respiration, and blood pressure. Today, it's used only as a topical anesthetic in the respiratory tract. Cocaine's rush quickly fades, which adds to the risk of continuous use and toxic effects.