How Long Does It Take For Sea Urchin Spines To Dissolve?

You stepped on a sea urchin. It has probably hurt a lot and now you wonder how to get rid of the spines from your skin. Will they dissolve by themselves or do you need to seek for a doctor? In this article, I’ll answer all your questions but let’s start with a quick answer:

Sea urchin spines can dissolve within a few days, or weeks and the best way to speed up the process is to soak the wound in vinegar or hot water.

However, that certainly doesn’t tell the whole story. Below I’ll explain how to treat sea urchin sting and dissolve spines. I’ll explain how to clean the wound, then you should see a doctor, why does a sea urchin stings, and who to prevent it. Furthermore, I’ll tell you a little bit about the most venomous sea urchin in the world. Read on!

How to treat sea urchin sting and dissolve spines?

If you got stung by a sea urchin and see black spots on your stung body part, that means the spines have broken off under your skin. But don’t panic because spines will most likely dissolve over time by themselves. There are also ways to help the dissolving process like soaking a wound in vinegar. 

Follow the steps below to make sure you treat your wound properly and help the dissolving process.

Remove visible spines

First, try to remove larger spines with tweezers. If you got stung by sea urchin with long, black spines, like a very common Diadema, these calcium-filled spines are very brittle and easy to break. Therefore, once you remove larger pieces, you may see black spots on your skin that are spines broken off within your body. 

If you got stung by a short-spined sea urchin with pedicellaria, you might want to scape out them with razors gently. These toxic claw-shaped appendages with movable jaws can get stuck into your skin.

Remove spines under your skin

To remove spines that have broken off within your skin, try to soak them in vinegar. Vinegar is a substance that contains acid and can dissolve spines that are made of calcium carbonate, just like in an experiment with an egg’s shell. Spines will absorb the acid and eventually dissolve.

To do that, simply grab a white or apple cider vinegar and pour it into a wound directly or into the basket where you can soak your wound. Repeat that process several times and observe if spines are disappearing. Then, make sure you keep your wound clean to avoid infection.

You can also grab a towel or gauze and soak it in vinegar. Next, apply the compress to the area with spines. If you can’t remove all spines, soak the wound several times a day and spines should eventually dissolve. It may take a few days or weeks.

In addition to that, the acid in vinegar kills the bacteria. However, it can only kill or reduce certain types of gems like E. coli and Salmonella, so if you have a proper disinfectant available, make sure to use it and clean the wound. 

If you don’t have vinegar available, use hot water as hot water is very effective in reducing the pain, can soften sea urchin spines, and eventually help in dissolving them as well.

Clean the wound

Make sure you clean the wound by using running water or water with soap to get rid of the dirt and debris. Next, use a disinfectant to disinfect the wound. This can prevent the infection that can cause complications later. Do not apply a bandage – leaving the wound uncovered will help in healing.

When should you see a doctor? 

If you’re experiencing pain for longer than a few days, you should see a doctor. Sometimes, the spines left in your skin can migrate elsewhere deeper in the body, causing tissue, bone, or nerve injury. In case this happens, it may require surgical removal.

Some people may experience an allergic reaction right after being stung or are stung by a highly poisonous sea urchin (like a flower sea urchin). Several symptoms may require you to seek immediate emergency attention:

  • Difficulty breathing, 
  • Extreme fatigue,
  • Muscle weakness and aches, 
  • Changes in a heart rate
  • Loss of consciousness, 
  • Dizziness or paralysis

In case this happens, it’s a medical emergency, and you should call 911 immediately.

Why does a sea urchin sting?

Sea urchins use their spines to protect themselves from predators. They have a defense system made of sharp, long, venomous spines and shorter spines called pedicellariae. It may be hard to notice, but sea urchins constantly move their spines. They move them because they want to directly point them at predators when shadows pass over.

Sea urchins however are not predators to humans and they will not attack. They move very slowly and will sting only when we step on them and their venomous spines will break into our skin. We need to be careful walking or swimming on the rocky shores to avoid them.

How to prevent a sea urchin sting?

To prevent sea urchin sting, you may want to wear water shoes, especially on rocky beaches where sea urchins hide under rocks and may be hard to notice.

Try to avoid areas where you see a large number of sea urchins or where people often get stung by them. It’s also worth knowing that sea urchins come out of their shelters at night, so swimming in a rocky area at night can be riskier.

You can notice that especially on the night dives if you’re a diver. You need to be very careful and don’t get too close to the seafloor that you can’t see clearly. Once I turned off my flashlight to play with the bioluminescence with many sea urchins below me (which I didn’t know). I sank a meter down and you can guess what happened next 🙂

So, always be aware of your surrounding when underwater.

The most venomous sea urchin

After getting stung by a sea urchin we feel pain and the stung area may become red and swollen but it is usually nothing seriously dangerous (considering we’re not allergic to its venom). However, there are sea urchins species more dangerous than others. One of them is called flower sea urchin (Toxopneustes pileolus).

Flower sea urchin

The flower sea urchin can be found in the Indian and Pacific oceans. It’s known for being highly dangerous, as it can deliver excruciating stings when touched. Its common name comes from its flower-like pedicellariae, which are usually pinkish or yellowish-white to yellowish-white. These “flowers” are very venomous, and this is why its generic name (Toxopneustes) translates to “poison breath”.

After getting stung by this sea urchin, the reported symptoms are severe debilitating pain, muscular paralysis, breathing problems, numbness, and disorientation. It’s extremely dangerous to get stung by a flower sea urchin while swimming or diving because it can result in an accidental drowning. The flower urchin was named the “most dangerous sea urchin” in the 2014 Guinness World Records.

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