Symptoms and Signs of Sea Urchin Stings and Puncture Wounds

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 10/11/2021

Doctor's Notes on Sea Urchin Stings and Puncture Wounds

Sea urchins are non-aggressive marine animals that have round-shaped bodies covered with spines. They live in wave-exposed rocks and shallow, sandy areas. People may accidentally step on them in the shallow surf, or they may pick up the urchins, not realizing the spines could cause injury. Sea urchins have two types of venomous organs - spines that produce puncture wounds and pedicellaria, which are small, delicate seizing organs that lie between the spines and release venom when they attach to an object.

Symptoms of a sea urchin puncture wound may include

  • swelling and
  • redness around the area, which may lead to severe pain and infection.

If a person has multiple sea urchin puncture wounds, symptoms may include

  • fatigue,
  • weakness,
  • muscle aches,
  • shock,
  • paralysis, and
  • respiratory failure, which can be fatal.

What Is the Treatment for a Sea Urchin Puncture Wound?

Sea urchin stings are very painful but rarely severe. Avoidance of sea urchins and their barbs is very important. First aid for a sea urchin sting includes:

  • Immerse the affected area in freshwater as hot as the injured person can tolerate
    • Renew the hot water several times over the course of an hour
  • Remove any large spines
    • The smaller pedicellaria may be removed with tweezers or gently scraped with a credit card or razor and shaving cream
  • Clean the wound thoroughly with soap and freshwater after spine removal
  • Use over-the-counter (OTC) pain medications such as acetaminophen (Tylenol) or ibuprofen (Motrin, Advil) for pain
  • Antibiotics are not necessary right away for sea urchin stings but watch the wound closely for signs of infection such as:
    • Redness
    • Pus
    • Red streaking
    • A sudden increase in pain
    • Fever
  • Some stings, especially multiple stings, can cause severe symptoms and can be fatal; seek medical care for multiple punctures

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Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.