I read a couple of blog posts about healing potions and thought I'd spew a few thoughts out on the subject. 5E with its short and long rests really made healing potions somewhat unnecessary, that's the nut of the problem. Then if you do swig one you get only a little healing and could roll a 1.
Dojo Darelir, the School of Xenograg the Sorcerer suggests you get one-quarter of a character's Max HP which matches 4E Healing surges.
Nerdwerds thinks a Healing potion should bring you back up to Max HP (but cost a lot).
I like Nerdwerd's solution but I have a different solution. Keep the price the same but if you suck up to many healing potions you develop some kind of immunity to the things. Imagine if Healing Potions had a Usage Die that started at Ud20. You roll the die, and your CON modifier and that's how much you heal. You still might get super-low numbers but not every potion is gonna be freshly brewed and sometimes the alchemist might have used a shortcut of putting in Toadstool instead of Mandrake and what are you gonna do.
So at low level you have a good chance of healing big and that's when your trying just to stay alive. But the more you drink the more likely you roll a 1-2 and when that happens the usage die drops so that your next healing potion only cureds Ud12, then Ud10. By the time your high enough level you probably don't need healing potions anyway.
