Debuffs are a feature first introduced in patch 1.0.6. Debuffs bestow negative effects upon their bearers, and unlike Buffs, cannot be removed by right-clicking on their icons. There are several accessories which provide immunity to a single Debuff, which build into the Ankh Charm, giving immunity to many debuffs. Some Monsters can be infected with certain debuffs, including Confused, Cursed Inferno, On Fire! and Poisoned.
Debuffs will naturally wear off after a short period of time, though some may last up to a few minutes. The Nurse can cure debuffs at the cost of 7 50 per debuff.
In 1.2, many new accessories were added which prevent one specific debuff each, and can be combined at a Tinkerer's Workshop to create versions that give immunity to all the debuffs of their components.
|Icon||Name||Inflicted By||Tooltip||Duration||Effect||Prevented by|
|Blackout||Light vision severely reduced||4 seconds||Screen is reduced to almost complete darkness||None|
|Bleeding||Cannot regenerate life||45 seconds||Prevents natural health regeneration||Adhesive Bandage|
|Broken Armor||Defense is cut in half||2 minutes||Defense is reduced by half||Armor Polish|
|Losing life and slowed movement||Until losing contact||Movement speed halved|
10 health lost per second
|Chaos State||Rod of Discord||Using the Rod of Discord will take life||8 seconds (since 1.2.3)||Using the Rod of Discord deals damage equal to 16.67% of the player's maximum health||None|
Spiked Ice Slime
|Your movement speed has been reduced||10-20 seconds|
45 seconds (Ice Golem)
|Movement speed halved ||Hand Warmer|
|Confused||Movement is reversed||7 seconds||Player movement is temporarily reversed|
Confused monsters will flee
|Cursed||Cannot use any items||4 seconds||Prevents the player from using items||Nazar|
|Losing life fast.||7 seconds||4 health lost per second||None|
|Darkness||Decreased light vision||15 seconds||Decreases the player's vision||Blindfold|
Melee and Ranged damage with Frost Armor
Flower of Frost
|It's either really hot or really cold. Either way it REALLY hurts.||4 seconds|
|6 health lost per second|
Negates health regeneration
|Frozen||Spiked Ice Slime|
|Frozen in place||2 seconds||Encases the player in ice, rendering them helpless||Hand Warmer|
|Horrified||Wall of Flesh||You have seen something nasty, there is no escape||While fighting the Wall of Flesh.||Causes the player to die if they leave the underworld||None|
|Ichor||Ichor Sticker (Ichor Stream)|
|Reduced defense||15 seconds||Reduces players current defense by 20||None|
|Mana Sickness||Consuming any Mana Potion||Magic damage reduced by x%||5 seconds||
Magic damage is reduced by 25% but will fade out to 0% and then end
|Midas||Flask of Gold|
|Drop more money on death||15 minutes||Increases money drops for the player and monsters||None|
|On Fire||Slowly losing life.||3-7 seconds||4 health lost per second||Water, Honey|
Obsidian Skin Potion
Lava Waders 
|Poisoned||Slowly losing life||7-10 seconds||2 health lost per second||Bezoar|
|Potion Sickness||Consuming certain healing items ||Cannot consume anymore healing items||60 seconds||Prevents the player from consuming healing items||Philosopher's Stone|
(reduces time to 45)
|Silenced||Cannot use items that require mana||7 seconds||Prevents the player from casting any spells||Megaphone|
|Suffocation||Losing life||Until free from gravity-affected (sand, silt etc.) blocks||10 health lost per second||None|
|Slow||Movement speed is reduced||15 seconds||Horizontal movement speed halved ||Fast Clock|
|The Tongue||Wall of Flesh||You are being sucked into the mouth||While being dragged by the Wall of Flesh||Wall of Flesh pulls the player in front of itself|
Unable to move or use items
|Tipsy||Ale, Sake||Increased melee abilities, lowered defense||2 minutes||2% increased melee critical hit chance|
10% increased melee attack speed
10% increased melee damage
|Losing life||8 seconds||4 health lost per second||None|
|Water Candle||Water Candle||Increased Monster Spawn Rate||Until out of range of Candle||Enemy Spawn rate increased||None|
|Weak||Physical abilities are decreased||5 minutes||
|Wet||Water Gun||You are dripping water||25 seconds||-||None|
- ↑ 1.0 1.1 Debuff nullified by running
- ↑ The following monsters can inflict the On Fire! debuff: Fire Imp (Burning Sphere), Lava Slime, Meteor Head, Skeleton Archer (Flaming Arrows)
- ↑ The following weapons can inflict the On Fire! debuff: Fiery Greatsword, Flamarang, Flamelash, Flamethrower, Flaming Arrow, Flower of Fire, Molten Fury, Molten Hamaxe, Molten Pickaxe, Sunfury
- ↑ These items will only give protection against the On Fire! debuff inflicted by Lava, as well as lava damage. They will not protect against the debuff from other sources.
- ↑ The following weapons can inflict the Poisoned debuff: Blade of Grass, Poisoned Knife, Thorn Chakram, Tonbogiri.
- ↑ The following healing items will inflict the Potion Sickness debuff: Bottled Water, Glowing Mushroom, Goldfish, Greater Healing Potion, Healing Potion, Lesser Healing Potion, Lesser Restoration Potion, Mushroom, Restoration Potion
- When curing the Potion Sickness debuff via the Nurse, the icon disappears but the actual effects of the debuff are not removed.
- The Bleeding effect can be overridden by the Campfire effect and various accessoires.
- Added Mana Sickness and Wet.
- On fire! debuff now causes the player's hair to fade to crisp black, depending on how low their health is.
- Added Chaos State
- Debuffs now properly stack on monsters in multiplayer
- Water Candle now provides a visible debuff
- Added Chilled, Frozen, Ichor, Venom and Blackout debuffs.
- Broken Armor debuff now lasts for 2 minutes, down from 5.
- Added to the game.