Which substances are classified as Schedule 1 drugs?

Schedule I drugs are substances that have a high potential for abuse and have no accepted medical use in the United States. They are often classified as having a lack of accepted safety for use under medical supervision. The substances listed in the correct answer, which include heroin, marijuana, and LSD, fall into this category due to their significant risks of abuse, addiction, and potential for severe adverse effects.

Heroin is an opioid derived from morphine and is associated with a high potential for addiction. Marijuana, although increasingly accepted in some areas for medicinal use, remains classified as Schedule I at the federal level, indicating that it is perceived as having high risks. LSD, a powerful hallucinogen, also falls under this classification due to its potential for abuse and unpredictable psychological effects.

In contrast, the other options listed include substances that are either commonly prescribed for legitimate medical conditions or have accepted medical uses. Morphine and codeine, for example, are Schedule II drugs, which do allow for medical use but still carry high abuse potential. Meanwhile, Ritalin, Adderall, Prozac, and Zoloft are classified differently because they are prescribed and regulated under other schedules that acknowledge their medical applications, even if they may also have potential for misuse in some populations