While the opioid epidemic engulfing the United States and the globe is well-documented, the potential use of powerful fentanyl derivatives as a weapon of terror is increasingly a concern. Carfentanyl, a powerful and deadly fentanyl derivative, is seeing a surge in popularity as an illegal street drug, and there is increasing congressional interest surrounding the classification of opioid derivatives under the Chemical Weapons Convention (CWC) given their potential to cause harm. The combination of the potency of opioid derivatives along with the ease of accessibility poses a potential risk of the use of these deadly agents as chemical weapons, particularly by terrorist organizations. Disaster Medicine specialists in recent years have established a sub-specialty in Counter-Terrorism Medicine (CTM) to address and research the unique terrorism-related issues relating to mitigation, preparedness, and response measures to asymmetric, multi-modality terrorist attacks.