Resurrection do not happen twice faster
Like many old words in the past: Nothing is perfect. Although the Enlifer is an ideal drug of immortality or a second life—many patients don't know, it still has a limitation. That's why it must be used with a certain amount per dose, as same as every person get most of the time. But what happens if you take it too much?
Typically, the substance will cease to exist within a few minutes. The more you were injected, the longer its lifespan. It can also generate heat while fixing your organs or in most cases - thawing your bodily fluid.
If your dead body are being injected with a large dose in a short amount of time, it would cook you into a steak. If you're alive and healthy, it will continue enhancing all the internal systems to work better—better than your body can handle.
And so the mutation began. It's a little bit noticeable at first until a handful of time passed when the progress becomes obvious. Each person face different cases; From a little sickness like a minor tumor or memory loss, to something randomly uncontrollable. Bones grown, muscle grown, face morphed, brain corrupted—concluding yourself into something monstrosity.
You might have the healthiest body you ever had in your entire life, then the next week you become nothing but the beast.
If the effect is not much, a simple treatment would be okay (A surgury may be acceptable). For those who became monster, even the best doctor can't do. The only way you can do is resting in the Sandman General Hospital for life.