Cocaine (benzoylmethyl ecgonine) is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. Aggrawal, Anil. Narcotic Drugs. National Book Trust, India. (1995) The name, cocaine, comes from "coca" in addition to the alkaloid suffix "ine," forming "cocaine" and is both a stimulant of the central nervous system and an appetite suppressant.
The effects caused by the use of cocaine include euphoria, excitation, feelings of well-being, general arousal, increased sexual excitement, dizziness, self-absorbed, increased focus and alertness, mental clarity, increased talkativeness, motor restlessness, offsets fatigue, improved performance in some simple tasks, and loss of appetite. Higher doses may exhibit a pattern of psychosis with confused and disoriented behavior, delusions, hallucinations, irritability, fear, paranoia, antisocial behavior, and aggressiveness.
According to NHTSA the observed signs of impairment in driving performance have included subjects speeding, losing control of their vehicle, causing collisions, turning in front of other vehicles, high-risk behavior, inattentive driving, and poor impulse control. As the effects of cocaine wear off subjects may suffer from fatigue, depression, sleepiness, and inattention.
In the DUI context as it relates to field sobriety testing, horizontal gaze nystagmus, vertical gaze nystagmus, and lack of convergence are not present. Pupil size is dilated and there is a slow reaction to light. Pulse rate, blood pressure elevated, and body temperature are elevated.