How Continued Drug Use Leads to an Overdose

How Continued Drug Use Leads to an Overdose

Drug overdoses are the top cause of accidental death in the United States

Drug overdoses aren’t always fatal, but death is common. An overdose is the body’s response to a toxic level of chemicals and often occurs when a person develops a drug tolerance and takes too much of a drug to get a desired affect.

Drug Overdose Basics

Signs of a drug overdose include the following several symptoms:

  • Problems with vital signs (temperature, pulse, rate of breathing, blood pressure)
  • Sleepiness, confusion, coma
  • Unusual skin temperature: moist and cool or hot and dry
  • Chest pain
  • Abdominal pain (nausea, vomiting, diarrhea)

Overdoses require immediate medical attention, and it’s important to know what substance a person ingested as well as how much of it and at what time.[1]

Drug overdoses are the top cause of accidental death in the United States and cause more deaths than traffic accidents, according to the Centers for Disease Control and Prevention. More than half of the drug overdose deaths in 2013 were related to prescription drug use, mostly opioid drugs. Of the 43,982 total overdose deaths, 52% were due to prescription drug use with 71% of that number due to opioids (OxyContin, morphine, oxycodone, etc.) and 30% due to benzodiazepines (Xanax, Valium, Ativan, etc.).[2]

The U.S. Food and Drug Administration recently approved wider distribution of a drug that reverses the effects of an opioid overdose. The Narcan nasal spray can stop or reverse the effects of an opioid overdose, giving people a faster version of the drug.[3]

Why Drug Tolerance Develops

An overdose may be intentional or accidental. When it is accidental, it may be the result of a person taking too much of the drug because he needs more of it to feel something. This process is called tolerance. On the most basic level, a person develops tolerance to a drug after taking it for a certain period and then experiencing lower levels of a response to the same amount of a drug. Some types of drugs bring on symptoms of tolerance more rapidly. For example, heroin or morphine promotes tolerance quickly because of the way the drug binds to brain cells. The drug initially changes chemicals in brain cells to prolong the feeling of certain impulses, such as pleasure. Over time, the cells become used to the drug, and it takes more of it to create the same chemical response.[4]

Psychological Elements of Overdose

In addition to the well-known physical signs of tolerance, many researchers make a connection between environmental factors and tolerance. In a study of one person who died of a heroin overdose, researchers found the actual concentration of morphine in the person’s blood was the same as the previous day, but the patient took the drug in a different environment. The unusual circumstance of the setting contributed to the overdose, believe study creators. Studies of lab rats show rats that receive a typical dose of heroin in a new setting are significantly more likely to experience overdose symptoms than rats that are in an accustomed setting. The expectation of the dose and setting appear to affect the body’s reaction. Researchers believe the act of anticipating and preparing to take a drug affects the reaction of a person, particularly for a person who has developed tolerance of the drug.[5]

Need Help Finding Addiction Treatment?

Drug overdoses are a significant problem in the United States. The CDC and other health advocacy groups emphasize the importance of drug awareness as an important step in reducing the number of accidents and deaths. When a person becomes dependent or addicted to drugs or alcohol, responsible treatment addresses his physiological cravings as well as any psychological and social needs that may be at the root of his urge to take substances.

Do you need help for a loved one or yourself? If you are looking for a treatment that manages mental health and substance abuse issues, call us today for advice. Our admissions coordinators are available 24 hours a day, every day. We help people find the best fit for addiction treatment, including therapies that address a person’s needs for day-to-day support. Don’t wait to start the road toward recovery. Call our toll-free helpline, and get started on a fulfilling and enriching life.


[1] WebMd Medical Reference. (2014). Reviewed by Joseph Goldberg, MD. Drug Overdose Basics. Retrieved Jan. 17, 2016 from

[2] Centers for Disease Control and Prevention. (2015). Injury Prevention & Control: Prescription Drug Overdose. “Prescription Drug Overdose Data.” Retrieved Jan. 17, 2016 from

[3] U.S. Food and Drug Administration. (2015). FDA moves quickly to approve easy-to-use nasal spray to treat opioid overdose. Retrieved Jan. 17, 2016 from

[4] National Institute on Drug Abuse. (2007). Definition of Tolerance. “The Neurobiology of Drug Addiction.” Retrieved Jan. 13, 2016 from

[5] Gerevich, J., Bácskai, E., Farkas, L., & Danics, Z. (2005). A Case Report: Pavlovian Conditioning as a Risk Factor of Heroin “Overdose” Death. Harm Reduction Journal, 2, 11. Retrieved Jan. 13, 2016 from