
Claxon |

This is at best a maybe. Expect a lot of table variation.
The big problems are how does it carry it? How does it manipulate it? How does it open it, bring it to it's mouth, and drink it?
The answer is like that only bipedal creatures with arms could likely be able to use potions. But it's not clarified anywhere.
Now, if you want to spend your character's actions opening up a potion and pouring it in your animal companions mouth to drink I see no problem with it. Anything that can drink can use potions.
Activation: Drinking a potion or applying an oil requires no special skill. The user merely removes the stopper and swallows the potion or smears on the oil. The following rules govern potion and oil use.
Drinking a potion or using an oil is a standard action. The potion or oil takes effect immediately. Using a potion or oil provokes attacks of opportunity. An enemy may direct an attack of opportunity against the potion or oil container rather than against the character. A successful attack of this sort can destroy the container, preventing the character from drinking the potion or applying the oil.
A creature must be able to swallow a potion or smear on an oil. Because of this, incorporeal creatures cannot use potions or oils. Any corporeal creature can imbibe a potion or use an oil.
A character can carefully administer a potion to an unconscious creature as a full-round action, trickling the liquid down the creature's throat. Likewise, it takes a full-round action to apply an oil to an unconscious creature.

CampinCarl9127 |

I agree, expect massive table variation. Personally I wouldn't let a companion be smart enough to drink them themselves (even if physically possible).
As far as feeding it to the companion, just imagine trying to pour a glass full of water down your dog's throat. I would almost say that if you wanted to do that in combat you would need to teach it a trick.
But that's purely my personal take, not RAW. As above, expect table variation.

Kifaru |

I may start buying potions for my AC in the future, but so far the only times it has come up has been with found potions.
Once it was a bulls strength potion we found with a party full of Dex builds. Another time, we had aquired a bunch of potions of cure light and cure moderate and for the most part the only thing taking lots of damage was my AC. So we had potions that were just going to go away at the end of the scenario. I just wasn't sure if it was allowed to give them to my animal companion.