Tretonin is the greatest scientific discovery of the Pangarans, a drug that makes the immune system impervious to any ailment, allowing people to live in perfect health. When an archaeological discovery on Pangar sixty years ago uncovered a symbiote queen preserved in stasis, the Pangarans began medical experiments to duplicate the healing properties of the Goa'uld, and they had been breeding symbiotes in captivity for nearly 30 years to produce the drug. However, the purplish liquid, administered by regular injections, completely suppressed the normal human immune system, resulting in a powerful resistance to disease, but also a complete dependence on the drug. A genetic defect in the symbiote offspring caused the healing effects of the drug to break down, and with no antidote to reverse the suppression of the immune system, those taking tretonin faced death when the supply could no longer be maintained.
When they had begun their experiments, the Pangarans had not realized that the symbiote queen they had been breeding was Egeria, the founder of the Tok'ra movement, and she had deliberately passed on the genetic defect to her offspring in the hope that the research would be abandoned when the drug became untenable. However, in a final act of compassion, Egeria provided the solution to the genetic flaw, enabling Malek to develop an antidote to save the Pangaran population. Since then, the Tok'ra have refined tretonin specifically for the Jaffa physiology in the hope of ending the Jaffa dependence on symbiotes.
When Teal'c and Bra'tac lost their symbiotes in battle, the experimental tretonin was used to save their lives, and they now live without symbiotes but rely on regular doses of tretonin, usually administered through an aerosol injection. With continued testing and refining of the drug, tretonin has become a promising alternative to the dependence on symbiotes. The warriors of the Hak'tyl were among the first Jaffa to accept the use of tretonin to replace their symbiotes, and gradually other members of the Rebel Jaffa movement began to overcome centuries of indoctrination and to see tretonin as a promise of freedom from enslavement for all Jaffa. Since the fall of the System Lords, tretonin is even more widely used among the Jaffa, and several thousand free Jaffa use it regularly with no ill effects. It has also been administered to wounded Jaffa whose symbiotes can no longer heal them, including Volnek and Haikon of the Sodan. Given time, it is hoped that a solution will be found for the dependence on the drug itself.