The text for Nauseated states that:
"The only action such a character can take is a single move action per turn."
Does this also preclude swift, immediate or free actions?
This question brought to you by a Wizard wanting to use their Special ability Shift to escape from a cockroach swarm that's on top of them.
As you mentioned, the description of Nauseated clearly states that you can only take move actions, and a down-conversion of move->swift is not possible by RAW.
The only action such a character can take is a single move action per turn.
Take a look at the very similar Staggered condition, where free/swift/immediate are explicitly allowed, implying that needs to be the case.
A staggered creature may take a single move action or standard action each round (but not both, nor can he take full-round actions). A staggered creature can still take free, swift, and immediate actions. A creature with nonlethal damage exactly equal to its current hit points gains the staggered condition.
(emphasis mine)
People in this paizo thread point out that there are some class features and spells that imply that swift actions should be possible.
The Persistence Inqusition has this ability:
Inner Strength (Su): At 6th level, once per day, you may heal yourself as a swift action, healing 1d6 hit points for every two inquisitor levels you possess. When you use this ability, you can also remove one of the following conditions from yourself: blinded, confused, dazzled, deafened, frightened, nauseated, shaken, sickened, or staggered.
The "Range: Personal" spell cleanse:
This spell [...] ends any and all of the following adverse conditions affecting you: ability damage, blinded, confused, dazzled, deafened, diseased, exhausted, fatigued, nauseated, poisoned, and sickened.[...]
Personally, I find these arguments very weak. Neither of these abilities are specifically designed to counter Nausea, both are rather cleansing a broad variety of status effects. The spell argument is further compromised by the fact that casting spells is also explicitly forbidden while Nauseated, which definitely points to developer oversight, which are not uncommon[citation needed] with such an expansive ruleset. By extension, I guess the author of Inner Strength didn't expect the Persistence Inquisition not to work correctly.
Nauseated and Actions: Does the nauseated condition really mean what it says when it says “The only action such a character can take is a single move action per turn” or does it just mean I can’t take a standard action?
The nauseated condition really means what it says. You are limited to one move action per round, and not any other actions. Compare to the staggered condition, which says “A staggered creature may take a single move action or standard action each round (but not both, nor can he take full-round actions). A staggered creature can still take free, swift, and immediate actions.”
Quoting a bit more from the Nauseated page:
Nauseated creatures are unable to attack, cast spells, concentrate on spells, or do anything else requiring attention. The only action such a character can take is a single move action per turn
It seens to me that "anything" includes special abilities, such as as Shift. The RAW is pretty clear - if it is a move action that is not a spell, a attack, or anything that requires attention, you can do it while nauseated. You also can do only one of such actions per turn. Otherwise, you can't take that action.
So, no, you can't shift away. Your wizard probably will become food for some nasty DM critter pretty soon.
But... How about free actions? Can I drop something I'm holding, or maybe speak something? How about Immediate and Swift actions?
Pure-RAW, no, you can't. The rules are pretty clear that you can only do a single move action per turn. However, I would rule that, if the Free Action don't need attentiveness, then you can do it without problems. You wouldn't be able to load a bow, for example, but it would be okay to drop a bow or other stuff you would be carrying. I also wont permit immediate or swift actions, since then need a certain level of attentiveness to perform.
