From the last paragraph of the entry on Potions in the SRD/PRD:
"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."
Fair warning, folks: I'll be in the field for three weeks starting this friday, with part of that away from the internet altogether (probably starting around the 20th). Expect slower posting from me during that time.