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Overview of Chemical-Warfare Agents


James Madsen

, MD, MPH, Uniformed Services University of the Health Sciences

Last full review/revision May 2019| Content last modified May 2019

Chemical weapons are developed by governments for wartime use and include

  • Toxic agents (intended to cause serious injury or death)
  • Incapacitating agents (intended to cause only temporary, non–life-threatening effects)
  • Incendiary agents (intended to produce light and flame)

Toxic industrial chemicals, as produced for industry, are also capable of causing mass casualties. Some chemicals (such as chlorine, phosgene, and cyanide compounds) have both industrial and chemical warfare uses.

Toxic agents are divided into four major classes:

Incapacitating agents are divided into

Opioids, especially potent fentanyl derivatives such as those reputedly used by Russia against Chechnyan terrorists in 2002, can be considered incapacitating. Although their use is not typically intended to cause serious injury or death, they can easily cause death by stopping breathing when they are used as mass-casualty weapons. In mass-casualty situations, an aerosolized form of opioids will most likely be used. Larger-than-usual doses of naloxone, the rescue drug for opioids, may be needed to reverse the effects of fentanyl derivatives.

In high doses, incapacitating agents can cause serious injury or death.

Incendiary agents, designed to create light and flame, may also cause burns in large numbers of casualties.

In addition to their chemical names and common names, most chemical warfare agents also have a one- to three-letter North Atlantic Treaty Organization (NATO) code. For example, chloroacetophenone is a form of tear gas that is marketed as Mace® and has the code CN.

The views expressed in this article are those of the author and do not reflect the official policy of the Department of Army, Department of Defense, or the US Government.

Drugs Mentioned In This Article

Generic Name Select Brand Names
naloxone EVZIO

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