Always stock up on Revive Potions and some form of healing medicine. At the lower levels, you will only need the Healing Herb, which costs 2 Credits and restores 10 HP’s. As you gain more and more HP’s from Leveling up, you will need to start purchasing the higher Medicines.

Healing Herb...........2 Credits 10 Hit Points
Healing Potion.........9 Credits 50 Hit Points
Revive Potion..........10 Credits Revives you from The dead to 1 Hit Point
Sorta Super Potion.....21 Credits 120 Hit Points
Super Potion...........45 Credits 250 Hit Points
Advanced...............500 Credits 1000 Hit