To treat internal bleeding in Casualties: Unknown, inject procoagulant, use an L.R.D. or a makeshift L.R.D. on your chest, or eat helluce, because those are the only things in the game that slow it. Bandages and dressings do nothing for it, since there is no wound on the outside to wrap, and a chest drain is what clears the blood that pools around your lungs while it runs.
Casualties: Unknown simulates your blood and heart in detail, so an internal bleed is slow, quiet and easy to miss until you are already short of blood. This guide covers how to tell you have one, every item that treats it, how to use each one, and how to clean up the hemothorax afterward.
How to Tell You Have Internal Bleeding
Internal bleeding never shows on the paper doll in the health panel. Your limbs look fine, there is no teardrop icon on any of them, and yet your blood volume keeps dropping. That mismatch is the tell.
Check these three things in the health panel (the heart button in the bottom-left corner of the screen):
- The internal bleeding moodle. It shows two brown drops, and since the 6.0 update it changes with the severity of the bleed, so a darker, more urgent moodle means a worse bleed.
- The bleeding rate under your blood volume. The panel shows how fast you are losing blood in liters per minute. If that number is red and climbing while no limb is marked as bleeding, the blood is going somewhere inside you.
- Your breathing. A bleed that runs for a while builds hemothorax, blood collecting around the lungs. It lowers your maximum oxygen (the developer restored that effect in demo update 7.0) and slows your breathing.
What Causes Internal Bleeding
It comes from hard hits to the core of your body rather than cuts on a limb. Bad falls, explosions and gunshots that land on the head, chest or belly are the usual sources. Two causes catch people out:
- A badly hurt abdomen. The 7.0 patch notes confirm that low muscle health in the abdomen causes internal bleeding, so a belly that stays near zero keeps you bleeding until you heal it.
- Hard stimulant. Its own description warns that an overdose “entails weakness and internal bleeding.” Respect the stated dose.
Every Item That Treats Internal Bleeding
| Item | How to use it | What it does |
|---|---|---|
| Procoagulant | Drag the syringe onto a limb in the health panel | Slows blood loss across the whole body, internal bleeding included |
| L.R.D. | Drag it onto the chest | “Highly reduces internal bleeding” on the chest, and treats the limb it touches plus its neighbors |
| Makeshift L.R.D. | Drag it onto the chest | “Slightly reduces internal bleeding” on the chest |
| Helluce | Eat it from your inventory | “Might lessen internal bleeding,” also helps sickness, but heats you up |
| Chest drain | Drag it onto the chest | Does not stop the bleed; drains the hemothorax it causes |
The quoted lines are the in-game item descriptions. Here is how to get the most from each.
Procoagulant comes in a 100 mL auto-injector, and each use takes about a third of it. Its description warns that it is “likely to cause clotting,” because it thickens your blood. Give one dose time to work before you reach for a second: its effect builds over several seconds rather than landing at once, and stacking doses is how a bleed turns into a clot.
The L.R.D. is the strongest single fix. It needs at least 25 mL of L.R.D. serum inside to work, and on the chest it also treats the surrounding limbs, eases pain and disinfects. The makeshift version is much weaker against internal bleeding but still useful on the chest when it is all you have.
Helluce is a dry purple herb that drops from pop plants. It is light, easy to find in the later layers and costs nothing to use, which makes it the best backup. It raises your body temperature a lot, so eat it somewhere cool, or pair it with water.
Step-by-Step: How to Stop Internal Bleeding
- Open the health panel and confirm the internal bleeding moodle is showing.
- If you have a full L.R.D. with serum, drag it onto the chest. If not, inject procoagulant.
- Eat a helluce if the bleed is still showing after the first treatment has had time to work.
- Watch the bleeding rate under your blood volume. When it stops climbing and the moodle fades, stop medicating.
- If the hemothorax moodle appeared, drag a chest drain onto your chest. Its description says it is reusable “after some time,” so keep it after use.
- Eat, drink and rest so your body can rebuild the blood you lost, or use a blood bag if you are dangerously low.
Tips Most Players Miss
- Carry one internal bleeding fix from layer one onward. A single helluce weighs almost nothing and buys you time.
- Do the First Aid course. Since update 6.1 it unlocks once you reach layer 2 in a run, and it walks you through the health panel’s tools.
- Do not waste dressings. They treat external bleeding only; save them for the limbs that actually show a drop icon.
- Low blood pressure is the real killer. Losing blood drops your pressure, and very low pressure can push your heart into fibrillation, so treat the bleed before it gets that far.
- If the experiment’s belly is badly hurt, heal that limb as well, or the bleed keeps coming back.
Orsoniks also sold launch bundles with Barotrauma and Abiotic Factor. If you play those too, see our Barotrauma Home and Harbor news and Abiotic Factor’s official mod support.
Frequently Asked Questions
Do bandages stop internal bleeding in Casualties: Unknown? No. Dressings and bandages only treat bleeding on a limb’s surface. Internal bleeding needs procoagulant, an L.R.D. or makeshift L.R.D. on the chest, or helluce.
What is the fastest way to stop internal bleeding? A full L.R.D. used on the chest is the strongest single treatment. Procoagulant is the next best, and it also slows any external bleeding at the same time.
Why is my blood volume dropping with no wounds? That is internal bleeding. Look for the moodle with two brown drops and check the bleeding rate under your blood volume in the health panel.
What is hemothorax? Blood building up around your lungs from an internal bleed. It lowers your maximum oxygen and slows your breathing. A chest drain used on the chest reduces it.
Can I use procoagulant twice in a row? Only in an emergency. It thickens your blood, and its description warns it is likely to cause clotting, so wait for the first dose to finish working before you take another.
Where do I find procoagulant and L.R.D.s? L.R.D.s turn up in medical crates, container crates, drop capsules and life-pod chests, and traders sell them. Procoagulant is a trader and crafting item. Both can be crafted once your Intelligence is high enough, and the L.R.D.’s serum is crafted separately.