Which substance use is most likely implicated in a case presenting symptoms of agitation, dilated pupils, and increased heart rate?

The symptoms of agitation, dilated pupils, and increased heart rate are commonly associated with stimulant substances, particularly cocaine. Cocaine acts as a powerful stimulant of the central nervous system, leading to heightened levels of energy, increased alertness, and a state of agitation. One of its prominent effects includes the stimulation of the sympathetic nervous system, resulting in physiological changes such as dilated pupils and an increased heart rate.

Unlike stimulants, substances such as alcohol and heroin typically result in depressant effects, leading to sedation, muscle relaxation, and, in the case of heroin, miosis rather than mydriasis (constricted pupils). LSD, while it can cause anxiety or agitation, primarily induces visual and auditory hallucinations and does not consistently present with the heightened heart rate and pupil dilation seen with cocaine use. Thus, when evaluating the combination of the symptoms listed, cocaine emerges as the substance most likely responsible for these specific signs.