Med-X

Med-X is a chem in Fallout 3, Fallout: New Vegas, Fallout 4, and Fallout 76.

Background
Med-X is the brand name of morphine, a potent opiate analgesic that binds to opioid receptors in the brain and central nervous system, reducing the perception of pain as well as the emotional response to pain. The active ingredient acts as a general anesthetic that dulls pain throughout the body and typically causes listelessness and lethargy. In layman's terms, it's a powerful pain killer delivered via a hypodermic needle.

Given its usefulness, Med-X is one of the more widespread pre-War chems, providing pain relief and recreation across the continent. Morphinists can be identified by contracted pupils and involuntary spasms. Five doses of Med-X have the potential to be fatal with 15 guaranteeing a lethal overdose.

Med-X
Med-X is a potent pain killer that can be often be found in first aid boxes or abandoned medical facilities. The chem will increase the player character's damage resistance by 25%, but there's also a 10% chance to become addicted, which results in a -1 penalty to Agility and Intelligence.

Behind the scenes
 Originally, Med-X was named "morphine" in Fallout 3. However, on July 4, 2008, Fallout 3 was refused classification by the OFLC in Australia, thus making the game illegal for sale in the country due to the "realistic visual representations of drugs and their delivery method [bringing] the 'science-fiction' drugs in line with 'real-world' drugs." On September 9, 2008 Bethesda vice president of PR and marketing, Peter Hines, described the idea of the Australian version of Fallout 3 as a misconception, and said all versions of Fallout 3 will not include real world drug references. However, the name "morphine" is still used in the Japanese and Czech versions of the game. 