Ask DAN: Marine Life Injuries | Scuba Diving

Ask DAN: Marine Life Injuries

Whether it’s a painful, but relatively benign, urchin spine in your buddy’s hand or a life-threatening sting from a box jellyfish, marine life injuries come with the diving territory, and knowing not only basic first-aid skills but also how to deal with specific types of injuries can make victims more comfortable — and even save lives. At DAN, we get questions through our hotline year-round on a wide variety of marine life injuries. Some are exotic; most are fairly common. With that in mind, this month we’ll review some of the more frequent types of marine life injuries and their management.

Before treating someone for specific types of injuries you should always follow standard first-aid procedures. This means wearing protective gloves, checking the victim for vital signs and shock, and calling emergency medical personnel as soon as possible. Basic first-aid classes are commonly available through your local Red Cross or other training agencies.

Once you’ve provided basic first aid, it’s time to consider the injury and any special considerations that may apply. Most of the injuries divers receive fall into one of three basic categories: stings/envenomations, irritations and bites.

Stings and puncture-wound envenomations

Stings generally come from jellyfish and other creatures in the phylum Cnideria, such as fire corals and hydroids. These creatures wield specialized stinging cells called nematocysts that pierce the skin like tiny harpoons before injecting their toxins. The intensity of the sting varies with each species, as well as the diver’s sensitivity to the toxin. Sea urchins are the most common form of puncture-wound envenomation. Their hypodermic needle-like spines glide through neoprene and skin alike, usually breaking off under the skin. Other spiny creatures include stonefish, lionfish and stingrays. For either type of injury the treatment is essentially the same.

Flush the affected area with seawater: This will assist in removing dirt, sand, surface venom and pieces of nematocyst. Do not use fresh water; the change in salinity can cause undischarged nematocysts to “fire,” causing more stings.

Remove pieces of the offending organism, if possible: In the case of jellyfish or hydroid stings, use forceps or tweezers to remove any large tentacles still on the skin. To remove any embedded or small particles, apply shaving cream and shave the area with a safety razor or scrape it with a credit card—sticky tape applied and quickly removed works as well. Removing small spines lodged in the skin is often not worth the effort—they’ll dissolve eventually. For bigger ones, let a doctor take care of it.

Soak the affected area: Many types of venom will degrade in high heat. Once all pieces of the organism are removed, soak the affected area in water as hot as is tolerable for 30 to 90 minutes. If hot water is not available, instant hot packs can be substituted.

Monitor airway and breathing: Divers who are sensitive to marine venoms may have severe allergic reactions, potentially causing respiratory distress or arrest. Divers who know this about themselves may have medication—such as an epi-pen—on hand. In these cases, you can help them self-administer their own medication, but don’t substitute it with anything else. Otherwise, contact medical professionals, help them breathe comfortably, administer oxygen if possible and start CPR if their breathing stops.

Irritations & Abrasions

We frequently receive calls from individuals who experience itching, burning and redness of the skin after a marine encounter of unknown origin. Irritations often occur as a result of a brush with coral or sponges. Coral scrapes can be painful and sometimes difficult to heal because the living organisms in the coral can get into the wound and cause infections. Contact with a sponge can leave irritating fibers in the skin, producing an itching rash that can range from mild to severe, possibly with pain and blistering.

Control any bleeding: Use direct pressure or pressure bandages to stop the bleeding like you would any other flesh wound. If the wound is deep, the bleeding difficult to control or the affected part deformed (i.e., the rescuer sees anything that might indicate a dislocation or fracture), get professional medical care immediately.

Clear the wound of fragments: The best way to remove any coral fragments is to irrigate the wound with sterile water or a saline solution. If neither is available, clean drinking water will do. A 20cc syringe (without the needle) is an excellent way to flush the wound with enough pressure to remove particles. To remove sponge fibers, use a wide piece of tape to lift the particles out or shave the area with a razor, credit card or tongue depressor.

Clean the wound with antibacterial soap: Use regular store-bought antibacterial soap. Mixing hydrogen peroxide with the water will further help disinfect the wound and help remove fragments. Make sure to use new gauze pads, fresh paper towels or a clean cloth for this cleansing.

Apply antibiotic cream: After a thorough cleaning, use a topical antibiotic cream (or hydrocortisone cream if treating an irritation), and cover the wound with a sterile dressing or bandage. Pre-sized bandages out of the box are absolutely acceptable if you have the right size. Change dressings daily or as soon as they become wet or soiled.

Keep an eye out: Monitor the injured diver to ensure there are no signs of shock or allergic reaction. If either develops, get medical help.


Though many divers (and nondivers) think sharks are the big biters underwater, the truth is shark bites are relatively rare. In fact, a bite from any marine creature is rare and usually the result of mistaken identity or a defensive reaction.

Monitor the airway and breathing: Bites can sometimes induce respiratory distress, so pay special attention to ensure the victim has an open airway and continues breathing. If breathing difficulty occurs, provide the diver with oxygen if it’s available.

Control the bleeding: Use direct pressure and dressings or pressure bandages to stop the bleeding.

Clean it: Use good judgment with this step. Only clean the wound if it won’t make the bleeding worse.

Bandage it: Once the bleeding is controlled and the affected area is cleaned (if possible), protect the wound with a bandage; keep pressure applied if the bleeding isn’t fully under control.

Get help: Get bite victims to a medical professional right away.

It’s important to remember that while many symptoms of marine life injuries usually resolve and disappear after one to two days, sometimes they unexpectedly return. This can occur anytime from two to five days after the initial encounter, and the recurring symptoms can be worse than the initial onset. If you feel something strange, even days after you got out of the water, go to the doctor, and don’t forget to explain your diving activities, as they may prove helpful in diagnosis and treatment.

What is DAN?

Divers Alert Network (DAN) is a 501(c)(3) nonprofit medical and research organization dedicated to the safety and health of recreational scuba divers.

For diving emergencies, call the DAN 24-Hour Diving Emergency Hotline: (919) 684-4DAN (collect calls accepted).
For nonemergency questions, call the DAN Medical Information Line at (919) 684-2948.
Additional information can be found at