Which of the following is a general indicator of hallucinogen use?

The correct choice is heightened senses as a general indicator of hallucinogen use. Hallucinogens, such as LSD or psilocybin mushrooms, are known to alter perceptions and enhance sensory experiences. Individuals under the influence of these substances often report intensified visual, auditory, and tactile sensations, which can lead to vivid hallucinations and a distorted sense of reality.

Other options are less characteristic of hallucinogen use. Loss of coordination is more commonly associated with depressants or alcohol, which affect motor skills and balance. Agitation may occur in various contexts, but it is not specific to hallucinogens; it can be related to other substances or mental health issues. Increased appetite is typically associated with stimulants or marijuana rather than hallucinogens. Therefore, heightened senses stands out as the most direct and relevant indicator of hallucinogen use.