Ipecac

Ipecac is an unlockable passive item.

Effects

 * Replaces tears with explosive and poisoning projectiles fired in an arc.
 * Tears down - (Delay * 2) + 10
 * +13 Shot Height
 * +40 flat damage (See Effective Damage)
 * Tear size multiplier: 0.4x
 * -0.2 shot speed.
 * Minor range down.

Synergies

 * / : Blood beam now does poison damage. The character doesn't gain the Damage Up or Tears Down effects.
 * Isaac shoots Ipecac tears while charging Brimstone. Both Brimstone and Ipecac shots modify Isaac's damage and tear delay stat, meaning that Ipecac fires slower and Brimstone charges slower, but Brimstone does an extra 40*13 damage. Take care to pre-charge Brimstone so that the Ipecac shot is on cooldown as Isaac enters a room.
 * Blood beam has a chance to do poison damage and explodes on enemy or obstacle contact. Adds +2 damage, but does not modify Isaac's tear rate stat., when placed, will trigger the Ipecac-Brimstone explosions. (possibly a bug)
 * : The main tear splits into four explosive splash tears. The splash tears can still damage Isaac.
 * : Bombs explode on contact, do no damage to Isaac and become bombs. You no longer get +40 damage. With Jacob & Esau only the character with the items is immune to the explosions.
 * Dr. Fetus + Monstro's Lung: Renders Isaac no longer immune to his shots, also they will explode as soon as Isaac shoots.
 * Dr. Fetus + Sad Bombs: Isaac is not immune to the explosive shots created by the Sad Bombs' effect.
 * : Missiles turn green and are poisonous. Damage greatly increases as the flat damage bonus stacks with Epic Fetus' explosive multiplier.
 * : The Ipecac shots cause full-damage explosions instead of lesser splash damage when they bounce off the floor, though they can also harm Isaac.
 * : The ghost form uses Ipecac as normal. The skeleton form's melee attacks become poisonous and explosive with +4 flat damage; he cannot be hurt by the blasts but is pushed back by them. The charged boomerang attack is only poisonous.
 * The charged boomerang attack is now explosive while being sent out, but not while returning. These explosions still do no self-damage.
 * : Tear delay is increased by 1/3 compared to either of the items on their own, but Isaac now fires Ipecac shots that releases poisonous, high-damage but\non-explosive split tears on impact.
 * : Tear damage is increased by 4, explodes when killing an enemy, and comes back to Isaac.
 * +4 damage bonus, no explosion.
 * +2 damage bonus, no explosion.
 * : The ring has chance to do poison damage and explodes on enemy or obstacle contact.
 * : The explosions from the beam do not damage Isaac.
 * : Knife turns green, may poison enemies, and removes Ipecac's damage increase.
 * Also adds +4 damage.
 * Also adds +2 damage, explodes on enemy contact if thrown.
 * : Isaac fires a barrage of Ipecac shots, with no increase in charge time compared to Monstro's Lung alone.
 * Charge time increases by 3x.
 * : Leaves a massive pool of creep on the floor on impact.
 * : The Ipecac tear will spawn two smaller explosive tears when it collides with a solid object, but not with an enemy. These tears can spawn tears on their own as well, potentially leading to huge chain reactions.
 * : The laser ring becomes poisonous and gains +4 damage.
 * Explodes on contact, adds +2 damage.
 * : No damage bonus, poisonous laser.
 * +4 damage bonus, poisonous laser.
 * +2 damage bonus, poisonous laser that explodes on enemy or obstacle contact. Keeps Ipecac's stats other than damage.
 * Note: This combination is not advised if the player has the Multidimensional Baby familiar. When the ipecac technology laser passes through the Multidimensional Baby, it instantly explodes, damaging the player and likely being fatal for the run.
 * : The explosive tears from Ipecac are replaced with Trisagion's beams that travel through obstacles and have a piercing effect dealing 33% of regular damage to enemies they come in contact with, but won't explode on hit. The Ipecac explosion will happen once the beam runs out of range or hits a wall and will deal damage equal to Isaac's damage.
 * Keeps Ipecac's stats but shoots a constantly exploding Trisagion beam. There is no way to avoid being hit from the explosion, since the shot immediately explodes.
 * Brain Worm: The Ipecac tears will snap 90 degrees and rain down at nearby enemy should the shot miss, completely eliminating the shortcoming of having too much range and causing Ipecac tears to fly over enemy's head, missing them.
 * Chance of having razor replacing Ipecac tears, quadrupling the damage and causing the explosion to shake the room.
 * The laser will repeatedly explode on contact with an enemy or obstacle.

Interactions

 * / /  /  / : The damage multipliers from these items do not apply to Ipecac's +40 bonus, resulting in much lower damage increase than expected.
 * : Charged up Ipecac deals expectedly high damage. Rapid-fire can be used against weaker enemies or to clear obstacles when necessary.
 * / / : The damage multipliers from these items apply to Ipecac's +40 bonus, unlike others.
 * : Although damage is increased, the tears' hitboxes also grow larger which may be detrimental.
 * : If a fire is generated at the same time as an Ipecac shot, the Ipecac shot will explode instantly.
 * : As the Glass Cannon tears are so large, even a modest damage increase or a single tear size increasing item is likely to render the tear unable to damage enemies.
 * Guppy transformation: Blue Flies are no longer spawned on hit.
 * Ipecac shots now spawn Blue Flies on hit, both direct and indirect.
 * Sparks of electricity shoot out only when hitting a wall.
 * : If an Ipecac shot also happens to have the Little Horn effect, after destroying an enemy, it loses its explosive property and effectively is just a normal Little Horn tear.
 * : Ipecac shots will explode on contact with enemy shots.
 * / : Occasionally shoots backwards or in all 4 directions, with high risk of self-damage.
 * Piercing tears: Tears will still explode on enemy contact, nullifying piercing.
 * : Tears will bounce off walls and rocks and won't explode until they hit the ground. Not recommended, as self-damage is likely.
 * Spectral tears: Ipecac shots no longer explode on contact with obstacles or walls, making accidental self-damage less likely but it's more difficult to open secret doors.
 * Tainted Forgotten's melee attacks will explode. Tainted Soul is immune only to those explosions, and any further explosions caused by synergies will damage it.
 * : The +40 damage bonus is not affected by the Technology 2 multiplier making the laser very high powered, but only every other Ipecac shot is fired.
 * : High fire rate needed for explosive shots to be connected.
 * : Ipecac tears orbit around Isaac for a very long time. They land far enough to not cause self-damage, but that can be relied on only if Isaac is not moving and do not hit enemies.
 * : The Ipecac tear will always travel forwards along the beam, even if Isaac is moving forward as well. This makes it less likely for Isaac to get damaged by his tear.
 * Due to the nature of the Ipecac, all shots will have a 100% chance of leaving a fire at the center of the explosion. It will also no longer leave behind green creep and the explosion will be of normal color instead of green.

Trivia

 * "Ipecac" is a shortened name for syrup of ipecac, a powerful emetic (a substance used to induce vomiting). This name is itself derived from a shortening of the source plant's name, Ipecacuanha.
 * If Isaac's damage is above 100, Ipecac's explosions will shake the screen. This is just a visual effect.
 * This item is used in Suicide King (challenge #7).

Seeds
2Q6M EEZQ (First floor Treasure Room) BK3W 93F4 (Treasure Room adjacent to spawn) NNH2 XPNP (Treasure Room adjacent to spawn) Q47Z GX3W (Treasure Room adjacent to spawn) C139 L97X (Treasure Room adjacent to spawn) 8R72 734X (Treasure Room, 2 rooms left of spawn) HYDG 0PPY (First Treasure Room) 0ACX C07T (First Treasure Room) 3N3B BFWZ (Treasure Room adjacent to spawn)