Brain Fluid is a Key Item in Bloodborne.

brain fluid "Greyish amoeba-shaped brain fluid. Wobbles and bounces.

Extracted from a patient whose head expanded until that was all that they were.

In the early days of the Healing Church, the Great Ones were linked to the ocean, and so the cerebral patients would imbibe water, and listen for the howl of the sea. Brain fluid writhed inside the head, the initial makings of internal eyes.

Once, a young girl had an older brother who was determined to become a doctor, and so she wilfully became his patient. In the end, this led to their encounter with the Eldritch Truth, for which they considered themselves blessed.

We fail to realize our own latent potential, until the moment it is lost, and we sense its absence. Ironically, this is the very nature of insight, like the moment one licks one's own blood, only to be startled by its sweetness."

Brain Fluid Usage

  • Brain Fluid is given to Saint Adeline to progress an in-game quest to receive the Milkweed Caryll Rune. There are 3 places to find it.


  • Drops off the enlarged head at the highest point of the research hall on the uppermost catwalk in the corner across a crow. This is accessed after turning the main tower in the Research Hall. (Can be reached early by dropping to another platform close to where you reached the top level and climbing up another ladder)
  • Drops off the enlarged head on the middle platform that is guarded by a hunter and minigun user in a wheelchair.
  • After using the Balcony Key she gifts you after the second Brain Fluid offering, reload the map, and Saint Adeline will have turned into an enlarged head without a body. Kill her to get a third Brain Fluid. (Killing her before then will permanently remove her from the current NG cycle, as well as your one chance to get the Milkweed rune, and you will have to try again in the next one.)
  • This item can only be gotten once per enlarged head (including Adeline).
  • Hostile enlarged heads do not drop this.


  • Player note 1


Trivia goes here

*Note* Saint Adeline must be given the first 2 Brain Fluids before she will turn into a enlarged head herself. Returning to the Hunters Dream multiple times seems adequate to move her in between in between states which will cause her to ask for more Brain Fluid.

Tired of anon posting? Register!
    • Anonymous

      You don't need to use the key before reloading and her turning into a big head, just go back to the Hunter's dream a few times.

      • Anonymous

        You cant have any of the blood items that she gives, if you do she will tell you not to be greedy. After getting a vile from her you can use it and give her another brain fluid, instead of returning to the dream.

        • Anonymous

          I like the comment on insight. Something that you don't realize is there, but recognize it's absence. The phrasing there means something different. It's not that you notice that you've lost it, but that losing it changes your perception. You know something is different, but not why it's different. I think that's the what the " the moment one licks one's own blood, only to be startled by its sweetness." means. You're closer to beasthood, and now blood is addicting to you, but you don't know why. It just is. But it's because you lost something you didn't know you had.

          However, I think it also comments on the desire for insight. Several characters were seeking what we could call insight in the game. Micolash, seeking to be "granted eyes" from Kos, or Master Willem and the students of Byrgenwerth. I believe they thought this insight would elevate them to the "higher plane", like what Kos did to Rom. But insight is only known via it's absence, right? So they went further and further. Thinking they didn't have it yet, because if they did, they would transcended. But they did have it. They just didn't realize they had it. They searched endlessly for something they already had, and the more they got, the madder they went.

          It's just an idea. But I really like how this one piece of lore about insight opens the door to some cool theories.

          • you'll know when it's time to kill Adeline because she'll have escaped the chair and she'll be in the corner of the room next to the door. her death is awful :(

            • Anonymous

              Whoever made this page and didn't mention that you need to warp out before killing her deserves to get shot in the face

              • Anonymous

                Dont kill her after giving the two brain fluids! Keep reloading the area until her head is HUGE, otherwise she'll still be mortal and die permanently like she did for me

                • Anonymous

                  Oh one drops off Adeline and she respawns after thats cool, accept not when you forget to mention thats after giving her the first two and leading people to kill her early wherein she doesn’t respawn. Change the headass retard description.

                  • Anonymous

                    "The cerebral patients would imbibe water, and listen for the howl of the sea."

                    I wonder if this has to do with hyperhydration, or "water intoxication." When a person drinks too much water, their cells often become oversaturated, especially in the brain. This causes severe headaches, as well as delusions.

                    It seems also to tie in with the medical condition, hydrocephalus, in which an excess of spinal fluid and/or water in the brain causes a child's head to enlarge. In some cases, the skull becomes incapable of encasing the brain.

                    Which begs the question... Is there a possibility that "paleblood" is nothing more than water? Or at least, is paleblood simply the plasma within our blood, devoid of its cellular and genetic content? After all, much of the arcane attacks in the game are represented by either water or ice, and there's the obvious correlation to the "Bulwark Sea..."

                    • Anonymous

                      Hi there, Somehow I forgat to take which fluid guarded by hunter and then I opened living failures boss. Finally simon appeared. Is there any possible way to take it ??

                      • Anonymous

                        Each Brain Fluid has its unique description. The one listed us the description for the final one (from Adeline).

                        • Anonymous

                          The badge is in a room to the right where the chandelier falls go right of the staircase and go into a hallway where a brainsucker is and the corpse should be in that hallway

                          • Anonymous

                            the A.I is still dumb so make the hunter follow you up to the top of the stairs with no handlebars then either make him dash off or push him off with the combat axe

                            • Anonymous

                              I can't kill one of them. It just keeps on reviving immediately after I kill it and I can't get the fluid

                            Load more
                            ⇈ ⇈