I just got the dog as companion but he is hurt. How do I heal him? I have no medical kits and gave him all the food I have. Resting seems to help a little but I end up spending all my money on food The Hunger aspect of this game is a pain in the arse.
Weird, I always had tons of food on me pretty much all the time since most animals drop food.
If you want to heal him during combat you should be able to equip a stimpack to one of your "weapon" slots and heal him that way (though I hardly ever did this - I just ordered him to run once his health got too low).
That also works outside of combat - with any healing item, e.g. can of meat, stims, pills, other food, etc. It's weird that the only ones you can use via dialog are raw meat and the medikit though - you should definitely be able to feed him stuff like "corned meat" via dialog too, but we can't for some reason...
Still better than other companions, who for some reason only have the pills and medikit options via dialog (you'd think stims would be a dialog option as well - but at least they use those automatically).
BTW, I'd ensure your companions DON'T carry any healing chems except stims (and later only super stims). They're "smart" enough to use the weakest thing they have, which in the case of the pills can sometimes cause them to temporarily lose strength, which can suck during combat.