Everything can technically be considered "Drug" depending on the doses, even water. and depending on who you ask/definition you use. Generally if it affects normal bodily function it is a drug, although I would add a "and not required for normal bodily function" in order to exclude things like water and salt. When a person talks about "Drugs and alcohol" its usually in the context that implies "Illegal drugs, and alcohol". Alcohol not being illegal, but still having many traits associated with illegal drugs, means its a phrase commonly used. Its also why people generally talk about "Perscription Drugs, Illegal Drugs, and Recreational Drugs" in order to emphasis different context and problems associated with each. They are all drugs and many do similar things to your body. Some drugs even fall into all three categories (varying depending on where you live).