The standard treatment for radiation since the late 2100s. Even so, it was discarded in a special case whe Dr. Leonard McCoy discovered a cure for a hyerpaging syndrome on Gamma Hydra IV in 2267. In 2368, the drug was replicated to treat expected radiation illnesses on Gamelan V, and was pumped through the shipboard ventilation system of the U.S.S. Enterprise itself when radiation levels rose while towing a leaky, radioactive garbage scow. Even then, at the rate of radiation increase, it was effective for less than an hour. Later that year, up to four hours of radiation from a cargo bay plasma fire after the Enterprise's quantum filament collision caused only temporary physical damage but still required a few days of hyronalin treatments for those affected.