Pills

Pickups

Hearts

Coins

Bombs

Keys

Batteries

Pills

Cards

Chests

Sacks

Pills are pickups that can provide useful or inhibiting effects. They take up the same slot as cards and runes.

At the start of each run, an effect is randomly assigned to each color of pill. The pill effect for that color will remain constant throughout the run. (However, it is possible for PHDConverts all bad pills into good pills, spawns one pill pickup and restores health. Identifies all pills upon pickup. or VirgoGrants a chance to trigger the Book of Shadows effect upon taking damage, creating a shield that nullifies all types of damage for 10 seconds. Also converts "bad pills" into "good pills". to reassign some of the effects, such that 2 different colored pills will have the same effect.) The set of pill effects for any given run is usually known as the pill pool.

• The pill pool for each run has increased from 9 to 13.

Pill Effects

ID	Pill	Effect
0	Bad Gas	Isaac farts, poisoning enemies around him.
1	Bad Trip	Injures Isaac by a full heart. If a Bad Trip pill is used while Isaac only has a single heart left or less, the pill will turn into a Full Health pill instead. (This damage counts as red heart damage for the purposes of getting a Devil Deal.)
2	Balls of Steel	Grants Isaac two soul hearts.
3	Bombs Are Key	Swaps the values of Isaac's bombs and keys.
4	Explosive Diarrhea	Spawns five active bombs behind Isaac over a period of five seconds, at one a second.
5	Full Health	Refills every empty Red heart containers.
6	Health Down	Removes one red heart container upon use. While Isaac has one or fewer red heart containers, it will act as a Health Up pill instead. Blue Baby can encounter Health Down pills, even though he can't have red heart containers.
7	Health Up	Adds one empty red heart container upon use.
8	I Found Pills	Changes the appearance of Isaac's face. This pill is cosmetic only, and the effect disappears when you leave the room.
9	Puberty	Causes Isaac to grow four hairs from the top of his head and zits on his face. This pill is cosmetic only, and will stay for the rest of the run. Consuming three puberty pills will grant the Adult transformation.
10	Pretty Fly	Grants 1 fly orbital that circles the player, blocking projectiles and damaging fly-type enemies on touch.
11	Range Down	Decreases Isaac's range by 2.
12	Range Up	Increases Isaac's range by 2.5.
13	Speed Down	Decreases Isaac's movement speed by 0.12.
14	Speed Up	Increases Isaac's movement speed by 0.15.
15	Tears Down	Decreases Isaac's tears by 0.28.
16	Tears Up	Increases Isaac's tears by 0.35.
17	Luck Down	Decreases Isaac's luck by 1.
18	Luck Up	Increases Isaac's luck by 1.
19	Telepills	Isaac gets teleported to a random room. Has a small chance to teleport Isaac to the I AM ERROR room, and an extremely small chance to teleport him to the Black Market, like Undefined.
20	48 Hour Energy	Drops one to two little batteries and fully charges the spacebar item. Can be used with the Placebo or D1 to generate infinite batteries.
21	Hematemesis	Empties all but one red heart container and spawns 1-4 full red heart pickups. If Isaac only has half of a heart left, it will heal him to one heart. If used without any red heart containers, no health will be deducted, but red hearts will still spawn. If used in a Black Heart or Eternal Heart-containing Super Secret Room, it will spawn those types of hearts instead.
22	Paralysis	Prevents Isaac from moving for a short duration.
23	I can see forever!	Opens all entrances to the Secret Room and Super Secret Room for the current floor.
24	Pheromones	Charms all enemies in the room for a short period of time.
25	Amnesia	Replaces the floor map with a ? for the rest of the floor. If no other curses are active for the floor, the Curse of the Lost will appear under the level name when the map key is held. This effect cannot be negated by Black Candle. Also the only pill to have its flavour text appear on a piece of paper, like curses do.
26	Lemon Party	Spawns a large yellow pool (similar to Lemon Mishap) around your character. Greatly damages any enemy that steps on it, for 22 damage per tick or 66 damage per second.
27	R U a Wizard?	Tears are shot diagonally outwards for about 30 seconds. This effect does not reset upon exiting the room.
Afterbirth
28	Percs!	Gives The Wafer effect while in the room : reduces all damage taken to half a heart. Unlocked by completing Challenge #24: PAY TO PLAY.
29	Addicted!	Makes Isaac take a full heart of damage from all sources for the current room. Also changes his appearance for the room. Unlocked by completing Challenge #24: PAY TO PLAY.
30	Re-Lax	For a short time, poop spawns wherever Isaac moves, like Explosive Diarrhea but with poop. A higher move speed means you can touch more tiles in the same time. A pun on laxatives. Unlocked by completing Challenge #25: Have a Heart.
31	???	Gives the Curse of the Maze effect for the remainder of the floor. The effect can stack with other curses. If no other curses are active for the floor, Curse of the Maze will appear under the level name when Tab is held. This effect cannot be negated by Black Candle. Unlocked by completing Challenge #25: Have a Heart.
32	One makes you larger	Increases Isaac's size and decreases the pitch of his voice. This effect does not increase the size of Isaac's hitbox. These pills contribute to the Stompy transformation.
33	One makes you small	Decreases Isaac's size and increases the pitch of his voice. This effect decreases the size of Isaac's hitbox.
34	Infested!	Destroys all poop in the room and spawns a single Blue Spider under Isaac and on each destroyed poop.
35	Infested?	Spawns Blue Spiders equal to the number of enemies in the room. If there are no enemies in the room, spawns 1-3 Blue Spiders.
36	Power Pill!	Activates an effect similar to The Gamekid.
37	Retro Vision	Briefly pixelates the screen 3 times over 30 seconds.
38	Friends Till The End!	Spawns three blue flies.
Afterbirth †
39	X-Lax	Creates a pool of slippery brown creep underneath Isaac.
40	Something's wrong...	Creates a pool of black creep beneath Isaac.
41	I'm Drowsy...	Upon use, slows all enemies for the duration of the room.
42	I'm Excited!!!	Upon use, increases the speed of all enemies for the duration of the room. The effect triggers again 30 seconds after use and 60 seconds after use.
43	Gulp!	Upon use, any trinkets that the player is holding are destroyed, and their effects are permanently applied to the player. Unlocked by acquiring the Once More With Feeling! achievement: Complete a Victory Lap, defeating The Lamb.
44	Horf!	Upon use, Isaac shoots an explosive tear with the Ipecac effect that always deals 200 damage. Unlocked by acquiring the Dedication achievement: Participate in 31 Daily Challenges. (They don't have to be consecutive; it will still count if you die in the first room.)
45	Feels like I'm walking on sunshine!	Temporarily makes Isaac invincible, similar to Unicorn Stump. Unlocked by acquiring the Sin Collector achievement: Collect every entry in the Bestiary. (Bugged v190 - Mobs that don't exist in the bestiary are being counted. This allows Sin Collector to be unlocked without a complete bestiary.)
46	Vurp!	Throws up the last pill you used. Will spawn itself if no other pills were taken beforehand. Unlocked by acquiring the U Broke It! achievement: Obtain 50 items on a run (e.g., via two Steam Sales and Restock - Duplicate passives/familiars count towards the total, e.g., multiple Breakfasts).

Pill Appearances

ID	Pill
1
2
3
4
5
6
7
8
9
Afterbirth
10
11
12
13

Notes

• Among the attribute modifying pill effects, only five of the seven visible attributes are covered: health, range, tears, speed, and luck. Both shot speed and damage can't be altered by pills.
• Pill effects have a chance to be narrated upon use, as do cards and runes.
• Currently, the "Retro Vision" pill effect can crash the game on some machines, resulting in restarting the current floor when the game is continued.
• The "Addicted!" pill will have no effect if Isaac has The WaferAll sources of damage that would cause more than one half heart of damage are reduced to one half heart instead..
  • Despite this, if one takes both the "Addicted!" pill with "Percs!" in the same room, Isaac will take a full heart of damage from all sources.
• Having Midas' TouchEnemies that touch you are stunned and turn gold. Any enemy killed while in this state will drop a coin., MeconiumPoop has a chance to turn into black poop., or Hallowed GroundSpawns a white poop familiar, which turns into a white poop when Isaac is hurt. and using a "Re-Lax" pill has a chance to spawn golden poop, black poop, or white poop, respectively.
• Using an "Infested!" pill on red poop will spawn blue spiders and the red poop will regenerate.
• Using a "Gulp!" pill while holding two trinkets (with Belly ButtonDrops a random trinket. Grants a second trinket slot. or Mom's PurseAllows Isaac to hold 1 additional trinket.) will cause both trinkets to be absorbed.
• If a Tiny or Large Champion monster drops a "One Makes You Small"/"Larger" pill and either pill is not in the current pill pool, an existing pill will be overwritten. If the chosen pill was already identified, the new pill will also be.

Strategy

• Use of unidentified pills is recommended for outside of combat as Hematemesis, R U a Wizard?, Paralysis, Addicted!, X-Lax, and I'm Excited!!! can be detrimental mid-fight. However, I'm Drowsy..., Something's wrong..., Lemon Party, Bad Gas, and Pheromones are useless outside of combat.
• Percs! can be used in the Sacrifice Room to reduce the damage Isaac takes, potentially allowing him to do more sacrifices. However, if Isaac is teleported to the Devil/Angel room, he loses the effect.
• The invincibility effect from Power Pill and Feels like I'm walking on sunshine! can be utilized to get into Curse Rooms, play Blood Donation Machines, or use Devil Beggars without taking any damage.
  • Percs! can be used to reduce damage from these from Chapter 4 onward.

Unlockable achievements

• 

  Huge Growth - Increase in size 5 times in a single run. Sources of increased size include "One Makes you Larger" pills, XI - Strength, and Magic Mushroom.

• 

  Marbles - Use 5 Gulp! pills in one run.

• 

  Lachryphagy - Collect 10 "tears up" items or pills in one run.

• 

  Lil Spewer - Die to your own explosion from Ipecac, Bob's Rotten Head, or Horf! pill.

Trivia

• Lemon Party is an internet shock site featuring a group of elderly men performing oral sex.
• The Vurp! pill is a portmanteau of the words vomit and burp.
• Power Pills activating the Gamekid effect is a reference to Pac-Man, in which the "Super-Pac" powerup is obtained by eating a Power Pellet.
• "I Found Pills (and Ate Them)," "R U a Wizard?," and "I can see Forever" are all image macro memes.
  • Despite being called I Can See Forever, the effects only last for the rest of that floor.
• The Feels like I'm walking on sunshine! pill is a reference to the 80s song Walking on Sunshine.
• Balls of Steel is a reference to Duke Nukem; it is one of Duke's more famous quotes.
• Explosive Diarrhea is extremely loud and forceful diarrhea. In the original game, the message that displayed when the pill was activated was "Oh No!". The pill name and effect are likely a reference to Atomic Bomberman where a pickup of the same name would cause the player to drop bombs behind them uncontrollably for a short duration.
• Friends Till the End! was originally in the Wrath of the Lamb but removed in Rebirth, then put back into Afterbirth.
• Friends Till The End! is the only non-narrated pill.
• 48 Hour Energy is a reference to the drink 5 Hour Energy.
• X-Lax is a reference to the anti-constipation medicine Ex-Lax.
• "One makes you larger" and "One makes you small" are references to Alice in Wonderland, and the specific wording is a reference to the song White Rabbit by Jefferson Airplane.
• "Percs" is a reference to a street name for the prescription drug Percocet, which is more generically known as Oxycodone. This drug is meant to be used to treat pain, but it is often abused for recreational purposes.
• The "???" is the only pill which has 3 different narrated voice lines.