What eye indicator is typically found in someone under the influence of hallucinogens?

The indication that pupils will be noticeably dilated is correct for someone under the influence of hallucinogens. Many hallucinogenic substances, such as LSD or psilocybin, are known to cause mydriasis, which is the clinical term for dilated pupils. This physiological response occurs as a part of the body's reaction to the chemical compounds in these substances, which affect serotonin receptors and lead to various alterations in perception, mood, and thought processes.

In contrast, other effects such as constricted pupils are more commonly associated with opioids or certain depressants, and the presence of nystagmus, which involves involuntary eye movement, is typically linked to the influence of specific depressants or stimulants, rather than hallucinogens. Additionally, pupils that react normally would not be indicative of hallucinogen influence, as significant changes in pupil size are a typical physiological response when a person is under the influence of such drugs.