Which substance is commonly referred to as a "gateway drug"?

Marijuana is often referred to as a "gateway drug" because it is believed to be a substance that can lead individuals to experiment with more dangerous or addictive drugs. This term stems from various studies and anecdotal evidence suggesting that individuals who use marijuana are more likely to subsequently use harder substances, such as cocaine or heroin. Researchers have proposed that marijuana's popularity and relatively lower social stigma might facilitate the transition to other drugs, particularly among adolescents or young adults who are in a developmental stage that includes experimentation.

The concept of marijuana as a gateway drug has contributed to ongoing debates about drug policy, public health, and addiction treatment. Advocates for drug education and prevention often point to the potential risks associated with early marijuana use, linking it to an increased likelihood of trying other illicit substances.

Other substances listed, while they may have their own potential for addiction or abuse, do not typically share the same associations within societal discussions about drug use progression that marijuana does. Hence, marijuana occupies a distinctive position in this context.