At some point in the past, the Campbell Family managed to develop a cure for vampires. It was known to work, but by 2011 hadn't been used in "God knows how long" according to Campbell patriarch Samuel Campbell. Samuel called the cure "an old family recipe" and it was written down in Jebediah Campbell's Journal.
After Dean got turned into a vampire by Boris, he expected to have to be killed but Samuel informed him of the cure when he arrived. Samuel showed Dean the journal entry on the cure and assured him the cure would work despite Dean's skepticism. Samuel warned that they would need the blood of Dean's sire along with some other stuff he and Sam would have to get and that Dean could not drink even a single drop of human blood or the cure wouldn't work. After Dean left, Samuel expressed suspicion that Sam let Dean get turned into a vampire as Sam knew about the cure. Sam claimed that Samuel must've told it to Christian instead of him.
After Dean slaughtered Boris's nest, Samuel was able to prepare the cure for him. After Dean drank it, he experienced a series of flashbacks of his time as a vampire, including Sam seemingly allowing him to be turned and vomited up a lot of blood before he was human again.
A short time later, Dean remained suspicious of Sam letting him be turned into a vampire. After Veritas revealed that Sam was lying, even under her power, Sam admitted that he let Dean get turned into a vampire as he knew about the cure and that they could turn Dean back.
While investigating the vampires that had supposedly killed the families of Krissy Chambers, Josephine Barnes and Aidan, Dean found a young woman who had just been turned into a vampire. Realizing that she could still be saved, Dean stopped the young hunters from killing the young woman and told them that if they could get her sire's blood, they could use the cure to save the young woman. After Seth was taken down, the Winchesters created the cure which the young hunters administered to the young woman.
Following the deaths of Cody and Dale, Celia decided to turn her "daughter" Alex into a vampire. After the Winchesters and Jody Mills took down Celia's Family with Alex's help, the Winchesters created the cure to return Alex to humanity. The Winchesters warned Jody that Alex would need a few days to recover from the effects of the cure and Jody helped Alex recover, ultimately adopting her as Alex's only family was dead.
After Doug Stover is turned into a vampire by Marlon, Dean tells Sheriff Donna Hanscum that they can cure Doug since he hasn't yet fed. As Dean describes the cure, Marlon appears and states that his blood is the last ingredient. Donna kneecaps Marlon and orders Dean to collect his blood while she interrogates Marlon on where Terrance Clegg has gone.
As Dean and Donna race to rescue Sam and Wendy Hanscum, Donna feeds Doug the cure in the backseat of the Impala. Donna questions if the cure will really work and Dean informs her that the cure had worked on him. When Doug eventually wakes up, he is human once more, the cure having worked.
Most of the ingredients of the cure are unknown but when it was created to save Dean Winchester, Samuel Campbell stated that some of the ingredients they already had but some they would have to get, indicating that some of the ingredients are common enough, at least to hunters. On another occasion, Dean stated that two of the ingredients were garlic and sage. However, the biggest ingredient is the blood of the vampire sire. This blood is added last to the rest of the potion. Another necessary part of the cure is that the vampire must not drink even a single drop of human blood. If they do so, the cure won't work.
Once the cure is prepared, the vampire must drink it at which point they will vomit up a lot of blood and become human again. The cure is noted to leave the person who takes it sick for a few days. In at least one case, the person taking the cure experienced a series of flashbacks of his time as a vampire as the cure turned him human again. However, it is not known if this is a common side effect of the cure. In the case of Doug Stover, this did not happen, but he was unconscious at the time the cure was fed to him.
- Season 6
- Season 8
- Season 9
- Season 13
- Supernatural: Coyote's Kiss (mentioned only)
- Until the development of the werewolf cure, this was the only known monster cure in existence.
- In the non-canon novel Supernatural: Coyote's Kiss, Sam brings up the vampire cure and suggests that they do something similar to cure an insane Borderwalker. Dean's experiences with the vampire cure helps him figure out that they need the Alpha Borderwalker's blood for the Borderwalker cure.
- Unlike the werewolf cure, the vampire cure does not require the vampire sire in question to be still alive when their blood is extracted. As a result, the vampire sire is generally dead when the cure is prepared. The only known exception is Marlon who was still alive when his blood was extracted to cure Doug Stover.
- The vampire Marlon appeared to be aware of the vampire cure and what it entailed to be created.
- The vampire cure is one of two known monster-related cures developed by the Campbell Family. The other is the Djinn poison antidote.