Subnautica 2: How to Get Medical Gel Sac (Location & Uses)

TL;DR

• Medical Gel Sac comes from the Acid Raion plant — a purple, brain-like organism found in underwater caves.
• The closest plants are directly below and around your Lifepod, inside small cave systems.
• You can grab the Medical Gel Sac by hand — no tool needed.
• Always remove the Acidic Raion Pouches first using your Survival Multitool, or the plant sprays acid.
• Eating a Medical Gel Sac restores +10 HP. It is also used to craft the Enhanced First Aid Kit (+100 HP).

Medical Gel Sac is one of the most useful early resources in Subnautica 2. It heals you on the spot when eaten and goes into crafting the best First Aid Kit in the game. The good news is you do not have to travel far to find it. It is sitting practically right below your Lifepod from the very first minutes of the game. This guide shows you exactly where to look, how to harvest it safely, and what to do with it.

What Is Medical Gel Sac in Subnautica 2?

Medical Gel Sac is a harvestable resource found on the Acid Raion plant. It is the glowing green bulb sitting in the center of the plant, surrounded by the purple, brain-shaped pouches. You collect it by hand — no tool required.

When consumed directly, it restores +10 HP. That is a modest amount, but Medical Gel Sacs are plentiful and renewable, making them your go-to emergency heal in the early game before you have proper First Aid Kits set up.

Your character starts with 100 HP in Survival Mode. Health drops from starvation, dehydration, creature attacks, and environmental damage like extreme heat. Having Medical Gel Sacs in your quick-access slots early on can be the difference between surviving and dying on a tricky dive.

What Is the Acid Raion Plant?

The Acid Raion is the plant you need to find to get Medical Gel Sac. It is hard to miss once you know what it looks like. It is a large plant with bright purple, wrinkled, brain-like pouches clustered around a thick central stem. The glowing green bulb at the very top of that stem is the Medical Gel Sac.

The Acid Raion typically grows inside underwater caves and rocky openings in the ocean floor. It glows visibly in dark water, so once you enter a cave, you will spot it quickly.

Each plant has two harvestable parts:

• Acidic Raion Pouches – The purple brain-shaped sections. Harvested with the Survival Multitool. Each plant gives three pouches.
• Medical Gel Sac – The glowing green central bulb. Picked up by hand, no tool needed.

The plant respawns over time, so your early cave locations become reliable long-term farming spots.

Where to Find Medical Gel Sac

Medical Gel Sac is found throughout the starting region. You do not need to go far at all. The closest plants are almost immediately below your Lifepod.

Best Early Locations

• Cave directly below the Lifepod – Look for holes in the ocean floor under your starting position. Swim down into the shallow cave system and you will find Acid Raion plants within about 30 meters of where you start.
• Cave directly east of the Lifepod – About 30 meters away. There are two more Acid Raion plants in the lower level of this cave, just past the acid-spewing plant.
• Under and around the Welcome Centre – The Welcome Centre is roughly 70 meters southeast of the Lifepod. Multiple Acid Raion plants are clustered around and beneath this structure.
• Small caves throughout the starting biome – As you explore further, Acid Raion plants appear frequently inside any cave system in the early region. Once you have a few upgrades and can swim further, you will find them in large numbers.

The key thing to remember is that these plants are found inside caves, not out in open water. If you are swimming along the surface and not finding any, dive down and look for cave openings in the seafloor.

How to Harvest Medical Gel Sac Safely

This is important. There is a right order and a wrong order to harvest from an Acid Raion. If you grab the Medical Gel Sac before removing the pouches, the plant releases a burning acid cloud into the water around you. That damages your health and wastes the resource.

Here is the correct harvesting order:

1. Equip your Survival Multitool from your hotbar.
2. Approach the Acid Raion and cut away all three Acidic Raion Pouches first. Hit the sides of the plant, not the center.
3. Once all three pouches are removed, the plant is safe. Now grab the Medical Gel Sac by hand from the central stem.

If you follow this order every time, the plant will not release acid. The Acidic Raion Pouches you collect alongside the Medical Gel Sac are also very useful — do not throw them away. See our guide on how to get Acidic Raion Pouch for all the recipes they unlock, including the Basic Battery.

What Is Medical Gel Sac Used For?

Medical Gel Sac has a few important uses. Here is a full breakdown:

Eat Directly for +10 HP

You can consume a Medical Gel Sac straight from your inventory to restore 10 health. It is not a lot, but it is instant and costs nothing to use. Keep a few in your quick slots during early exploration for emergency top-ups.

Craft the Enhanced First Aid Kit (+100 HP)

The best use of Medical Gel Sac is crafting the Enhanced First Aid Kit at the Fabricator. This restores a full 100 HP in one use, making it the most powerful healing item in the game right now.

The recipe is:

• 1x Fiber
• 1x Medical Gel Sac

Fiber comes from Fibrous Pulp. See our guide on how to get Fiber and Fibrous Pulp if you need help sourcing it.

Craft the Basic First Aid Kit (+50 HP)

There is also a Basic First Aid Kit that restores 50 HP. It does not require Medical Gel Sac — only 1x Fiber. But the Enhanced version is worth prioritizing once you have a steady supply of Gel Sacs coming in.

Processor Alternative – First Aid From Medical Gel (+50 HP)

If Fiber is scarce, the Processor machine offers an alternative recipe. You can convert a single Medical Gel Sac into a +50 HP First Aid item without needing Fiber at all. This is a solid option in the mid-game when you want to stretch your healing supplies. See our guide on how to build a Processor for more details.

Important Note: You Cannot Craft First Aid Kits From the Lifepod Fabricator

The Fabricator inside your starting Lifepod is corrupted. It cannot craft First Aid Kits. You need to build your own base with a working Fabricator before the healing crafting recipes become available.

Until then, eat Medical Gel Sacs raw and pick up any pre-made First Aid Kits you find inside supply crates near wreckage and abandoned structures. See our guide on how to unlock the Habitat Builder and start building a base to get your Fabricator up and running.

Once your base is set up, check our guide on what to build in your base first so you prioritize the right crafting stations.

Other Ways to Recover Health in Subnautica 2

Medical Gel Sac is your main early healing item, but it is not the only option. Here is a quick overview of everything that recovers HP:

• Medical Gel Sac (raw) – +10 HP, no crafting needed.
• Basic First Aid Kit – +50 HP, crafted from 1x Fiber at the Fabricator.
• Enhanced First Aid Kit – +100 HP, crafted from 1x Fiber + 1x Medical Gel Sac.
• Processor First Aid (From Medical Gel) – +50 HP, crafted from 1x Medical Gel Sac at the Processor (no Fiber required).
• Prepared meals – Certain cooked dishes restore small amounts of health. Threemoon Temaki restores +15 HP and Pavlova restores +10 HP.
• Passive regeneration – Keeping your food and water levels high activates slow natural health regen over time. It is not useful in a fight, but it helps between dives at your base.

For the passive regen to kick in, you need to stay fed and hydrated. See our best early food sources guide and our guide on how to make water to keep your survival stats up.

Tips for Farming Medical Gel Sac

• Always remove the three Acidic Raion Pouches before grabbing the Medical Gel Sac. Wrong order equals acid damage.
• Do not discard the Acidic Raion Pouches. They craft into Basic Batteries, which power your Scanner, Flashlight, and other tools. See how to recharge tools and batteries.
• The cave below your Lifepod usually has two to three Acid Raion plants. One quick dive gives you enough Medical Gel Sacs and pouches for your immediate early needs.
• Plants respawn over time. Come back to the same caves regularly for a steady supply.
• Keep a few Medical Gel Sacs in your hotbar at all times during early dives. Ten HP is not huge but it can stop a death spiral when you are low and far from your base.
• Make Enhanced First Aid Kits as soon as you have a working Fabricator and Fiber. They are the best healing items in the game.
• If you are heading into deeper or more dangerous areas, stock up on healing items first. See our how to increase oxygen guide and our Improved Fins guide to help you survive tougher zones.

Thoughts

Medical Gel Sac is one of the simplest resources to find in Subnautica 2, and one of the most important early on. The Acid Raion plants are right below your starting area, the harvest is fast once you know the right order, and the healing value is solid for how little effort it takes. Get into the habit of collecting Gel Sacs every time you pass an Acid Raion plant, and you will never be stuck without emergency healing.

For a broader look at surviving the early game, check out our beginner tips and tricks and our best early upgrades and progression path. Subnautica 2 is currently in early access on Steam and Xbox Game Preview.