From Halopedia, the Halo wiki
Rejuverol is a brand of human drink commonly dispersed in bottles. It has been known to be provided to personnel that were awakened rapidly from cryosleep, helping them to quickly recover from its side effects.
Rejuverol has seen use within the United Nations Space Command for decades. In 2526, Staff Sergeant Avery Johnson was given a bottle following his rapid awakening from cryogenic stasis. During the Battle for Zeta Halo in late 2559, TJ Murphy was given a bottle of Rejuverol-10 when his group of survivors reached the makeshift UNSC base set up at the UNSC Mortal Reverie's crash site.
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