List of fictional medicines and drugs

Kalocin:

A universal wonderdrug stumbled upon by Jensen Pharmaceuticals. Kalocin is effective against every known virus, bacteria, fungus, and parasite, and even cancer. Research of Kalocin was halted and knowledge of it was covered up after it was discovered that anyone who stopped taking the drug quickly died from bizarre and massive infections "no one had ever seen before."

Source:
Wikipedia - List of fictional medicines and drugs
Wikipedia - The Andromeda Strain