Since the 19th century, drugs can both be used for instrumental or medical purposes and recreational use, when people only consume illegal substances to achieve some satisfaction. Speaking of instrumental drugs, medicals are obliged to follow specific rules on drug injection, which include dose calculations and ratio. In such a way, they ensure that the medicine cannot cause dependence and overdose. However, in most cases, when people use drugs for some individual purposes, their only ratio is their body that tells when and how much drug it needs. Statistics claim that in 2017, more than seventy thousand US residents died from drug overdose. Such numbers show that drug users, especially when in concerns substances like heroin and cocaine, are not aware of the drug dose acceptable for their body.
Drug abusers start consuming illegal substances for a variety of reasons. Generally, the most widespread factors are early aggressive behavior, drug availability at schools, lack of supervision, and low-income rates. As a consequence, people who obtain access to drugs because of mental issues or when they are relatively young are not aware of the ways how drugs work in their bodies. They only realize that a certain amount of drugs makes them try some new experience. Then, when people consume drugs for a particular period, their bodies become tolerant to the dose they usually receive, and users have to increase the number of drugs injected. With years of growing drug dependence, people rather follow instructions of their addicted body than the rules of drug consumption and hence, die from a drug overdose.