Spacemen can suffer from a lot of different status effects and temporary afflictions. This page will list them.
When knocked down the victim will drop items in hand, but will be able to crawl, pick up items and fight from the ground.
Common sources of Knockdown: Disarming, slipping
A paralyzed victim will fall down and be unable to act in any way, but can still talk.
A Stunned victim will not be able to move or perform actions of any sort, but will remain upright and will still be able to speak. Pure stuns are very rare, with Paralyze being mechanically identical and far more common.
Common sources of Stun: Goliaths
An Unconscious victim will have the same effects of Knockdown, plus the inability to see, hear or speak.
A Sleeping victim will have the same effects as an Unconscious one; the difference is that some things that can't help against Unconsciousness can reduce sleeping time, like coffee or being clicked on with help intent.
Other Status Effects
A Mute victim will be unable to speak or whisper until the Mute runs out. They will still be able to emote.
A Confused victim will sometimes take a step in a random direction.
Makes you vomit.
A Dizzy victim's screen will keep tilting until the effect runs out.
Common sources of Dizziness: Alcohol, Mushrooms, Diseases
Blurs your vision and makes you randomly fall asleep. Used to slow you down as well but that's bugged.
Common sources of Drowsiness: Chloral hydrate.
A Druggy victim's screen will display a colored overlay.
Common sources of Drugginess: Space Drugs, miscellaneous drugs
A Hallucinating victim will see and hear things that aren't there. Hallucinations can take many, many forms, with some being more subtle than others.
A jittering person's sprite will shake slightly.
Common sources of jitteriness: Electrocution, coffee overdose
Makes you stutter when trying to speak. Does not interfere with voice analyzer trigger recognition.