Unfortunately, or fortunately in Frost's case this health potion regardless of its high level didn't help with poison, disease, or illness otherwise it would have been used on Douglas the moment he became bed ridden.
Frost however, although impressed with the value and power of the high level health potion and filled with gratitude towards Leo for willing to use such a precious commodity was afraid.
'Low level health potions are bitter enough how bitter is a high level potion going to be?' Frost dreaded that possibility, but he didn't have a choice
Luna had already pulled the cork out and moved next to him gesturing for him to start drinking. Since he couldn't exactly move or grab anything he needed Luna to hold the vial and tip it upwards as he drank, meaning she'd also have control of the pace. If the flavour was diabolical, he wouldn't be allowed to stop drinking.
