Jellyfish Question

A reader writes (paraphrased by me): “Here in Corpus Christi, today, while surfing, I practically picked up a large man-o-war while surfing. The burn is intense as I write. I felt severe pain immediately. I panicked in the water. The tentacles clung on to me. I felt pressure on my heart and my feet began to itch. It was a long trip for a remedy, but I finally rinsed the burning skin with vinegar, but I think this made the pain worse as I began to have more pain in my joints and chest. I have been hit by a man-o-war before but never like this. I have been taking Tylenol to help with the pain.”

The victim’s experience invokes many of the nuances of jellyfish sting syndromes. First, the pain is typically described as burning, and begins immediately after the tentacles with their microscopic stinging cells make contact with the skin. When the tentacles wrap around the wrist and/or hand, the pain can be sufficient to cause muscle spasm, so that the ability to grip an object is lost. The “pressure in the heart” described by the victim might have been chest discomfort from the toxin, the cause of which is poorly understood. If the victim was in the age category for coronary artery disease, angina may have been invoked, which would be quite worrisome. It is possible to have a heart attack precipitated by a jellyfish sting, but this is quite rare. Itching in the feet makes one think about an allergic reaction, which is certainly possible after a jellyfish sting.

The victim reports that when he rinsed his skin with vinegar, he continued to suffer pains in his chest and joints. The vinegar would only be expected to diminish the skin pain, if it is effective at all, but not to have an effect on any systemic manifestation of the envenomation. So, if any venom that had entered the victim’s circulation was causing chest pain, joint pain, or any other symptom, topical vinegar would not be expected to have an beneficial impact on those particular problems.

From the description, this sounds like a significant, severe envenomation. Jellyfish stings are not to be taken lightly. I wouldn’t be surprised if this victim develops a prominent inflammatory response, which would have an entirely different set of manifestations, and subsequent treatment.

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Meat Tenderizer for a Jellyfish Sting

Anonymous has left a new comment on your post "Myths to Debunk":

"What about meat tenderizer for a jellyfish sting? I know that hot water works well as it causes the venom proteins to refold, but the usual folk treatment for Man 'o War stings here in Texas is a paste of meat tenderizer or to rub the area with a slice of fresh papaya or pineapple."

Great question. There are numerous remedies that have been recommended as effective against different "jellyfish" stings, but not many that have been tested scientifically in clinical trials. Furthermore, I have seen opinions change based on anecdotes and observation of just a few patients.

Here are some of the substances and methods that have been recommended for immediate treatment (not prevention) of jellyfish-type (e.g., jellyfish, Portuguese man-of-war, hydroid, fire coral, and others) stings, and my current understanding of what we know (or feel) about them:

1. Vinegar (household variety of white vinegar, which is acetic acid 5.0%, is recommended for stings from a box-jellyfish (Chironex fleckeri) and for many other stinging species. It seems to be a good all-purpose decontaminant. It can be cut 50% with water or isopropyl alcohol (see below) and retain its beneficial effect.

2. Isopropyl ("rubbing") alcohol has been observed by many users and practitioners to be effective against may stinging species. However, in at least one laboratory experiment, stinging cells (nematocysts) from jellyfish were observed under the microscope when flooded with isopropyl alcohol, and seen to "fire" their stinging apparatus. However, the meaning of this observation cannot be precisely determined, because it is not known whether the firing occurred with sufficient force to cause an envenomation (had the stinging cells been on a live tentacle placed against human skin), or even whether it was an agonal (occurring in the act of destruction of the stinging cells) activity caused by the alcohol. So far as I know, it has not been reported clinically that application of isopropyl alcohol worsens the sting of any marine creature. If anyone is aware of such a circumstance, please let me know.

3. Meat tenderizer. Most of these products contain papain, which breaks down proteins. This is perhaps the reason why an application of meat tenderizer is effective in diminishing the discomfort associated with the sting of a marine creature. However, one must take care to not leave meat tenderizer on sensitive skin for too long (e.g., longer than 10 to 15 minutes), because it can cause an irritating reaction in and of itself. Furthermore, I have heard from a few users that if the seasoned form of tenderizer is used, it may increase the irritation or even cause stinging with the initial application. The sensitive skin of infants and babies, and facial skin at all ages, may be more prone to an adverse skin irritation from application of papain. With regard to using application of fresh papaya fruit, I have heard that recommendation before. I don't know anything about the use of pineapple.

4. Other substances reputed to be of value are household ammonia, and lemon or lime juice. It's possible that the change in acid-base balance (pH) is what causes this effect, or perhaps it is some denaturation (destruction or inactivation) of protein or other components of venom.

5. Application of fresh water (e.g., tap water) has received mixed reviews. It is fairly well accepted that gentle application (e.g., pouring water without pressure or gentle rinsing under a tap) of fresh water worsens the situation, because fresh water is hypotonic (e.g., contains a lower concentration of salts) than sea water, and causes the stinging cells to "fire" and discharge their stinging apparatus, thus worsening the envenomation and pain. On the other hand, lifeguards in various locations have reported that the brisk spray from a shower or garden hose can be helpful. This is perhaps because the mechanical effect of the spray actually removes stinging cells and supercedes the deleterious effect of the hypotonic water. Application of cold packs, moist or dry, has received mixed reviews. The latest recommendation, which emanates from experts in Australia and other Indo-Pacific regions, is that application of hot water to tolerance can be helpful to treat a sting.

6. Solvents (e.g., acetone) are generally not useful and perhaps dangerous, both because of direct skin irritation and potential absorption of toxic chemicals through the skin.

7. The "pressure immobilization technique" was formerly recommended for stings of the Indo-Pacific box jellyfish (Chironex fleckeri), but has been removed from any formal recommendations, as it does not appear to be helpful, and may actually even be harmful.

One important point bears mention, which is that no topical decontaminant is foolproof, so it is absolutely essential to remember that prevention is extremely important. Whether one chooses to stay out of the water when stinging creatures are expected to be in the vicinity, wears a wet suit or "stinger suit," uses a topical sunscreen-jellyfish sting inhibitor, such as Safe Sea, or some other maneuver, it is much better to not be stung in the first place than to hope for success with any given treatment.

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Myths to Debunk

There are many myths related to outdoor medicine. These need to be “debunked,” so that people do not fall prey to outdated and useless techniques. Here are some of the most common myths (in italix):

1. Mechanical suction, electric shock, and immersion in ice water are effective first aid (“field”) therapies for snakebite. In truth, these are not only not helpful, they may be quite harmful. Antivenom therapy is the only therapy that has been proven effective, with the possible exception of pressure immobilization for certain elapid (e.g., coral) snake bites.
2. Urinating on a jellyfish sting is an effective method to reduce pain. This is of very limited value. Some persons will cite that it was helpful in their particular case, but at least as many persons will state that it did not diminish the pain. The most effective therapy is decontamination with a specific topical compound, such as vinegar or ammonia. The decontaminant chosen depends upon the species of stinging jellyfish.
3. Applying a cold pack to a jellyfish sting is the most effective method to reduce the pain. Current information indicates that application of warmth (e.g., immersion in non-scalding hot water) may be much more beneficial.
4. Rabies shots are injected into the abdomen and are horribly painful. Not true- post exposure rabies vaccination may include a painful component as rabies immune globulin is injected into the bite site, but the subsequent vaccine, which is administered as part of the post exposure treatment, is given as a series of very tolerable injections into the arm or thigh.
5. In any circumstance of frostbite, rapid rewarming is essential. Actually, this should only be done if the body part can be relatively guaranteed to remain thawed. Otherwise, re-freezing the tissue causes significantly more damage than does the initial episode of freezing.
6. The Heimlich maneuver should be used for any victim of submersion (near-drowning) to remove water from the lungs and improve the chance for survival. The Heimlich maneuver has never been proven to be of use in humans in this situation, and may in fact increase the risk for vomiting and harmful inhalation of gastric contents. There is no evidence that it removes water from the lungs.
7. Drinking large amounts of liquids is harmful during exercise because it promotes stomach cramps. Quite the opposite – so long as the ingested amounts are prudent and don’t promote nausea from a full stomach, it is essential to replace fluids and electrolytes constantly during periods of high exertion, particularly in the heat, to avoid dehydration.
8. A person struck by lightning is “electrically charged” and may not be safely touched. This is not true. It is perfectly safe to touch such a person, and in fact the sooner that breathing can be supported, the more likely that the victim will survive with maximal neurological recovery.
9. In cold water, it is better to remain in the water where one feels warm that to pull oneself onto a rescue vessel or platform and be exposed to wind chill. Absolutely not true – one may lose heat 25 times as fast in the water as in air, so no matter how uncomfortable you feel, if it is possible to get out of the water, do so.
10. Sharks and bears are attracted to menstrual blood, so it is important for women to avoid diving and hiking during menstruation. This is a false concept, and has never been proven to be true, either epidemiologically or scientifically.

photo by Jenny Hargrove

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A Jellyfish Tale

In May, I enjoyed a few days' diving in the Baja at La Paz, Mexico. At that time of year, the water is relatively cool and the visibility isn't perfect, but there is still much to see underwater as the nutrients arrive in the currents prior to the return of the big animals, such as hammerhead sharks and whale sharks. The dive operation at the Cantamar Resort was superb, so we were treated to swift and smooth boat rides to the dive sites, excellent dive guides, and wonderful lunches.

The surface of the water was generally flat, and our entries into the water were relatively easy, because there was little current and our group of divers worked well together. We played with sea lions underwater and saw countless pufferfishes, scorpionfishes, multi-colored moray eels, magnificent nudibranchs, bright starfish, barracuda, and stingrays, including a small manta and the bullseye electric ray Diplobatis ommata. As is my habit, I urged everyone to be careful and to avoid touching animals, sharp corals, or anything with which they were unfamiliar.

The sun was very hot, so it was important to use sunscreen and lip balm. I shared my supply of Safe Sea with everyone. This is a combination sunscreen-jellyfish sting inhibitor product that has been tested and found effective against many species of stinging creatures. When applied properly, it stays on the skin for 45 minutes to one hour underwater and is formulated to diminish or prevent stings from jellyfish or other similar creatures equipped with microscopic stinging cells. I never (well, almost never, as you will soon learn...) enter the ocean without covering my exposed skin with this product, because why not take every advantage to not be stung? Jellyfishes and other marine stingers are often effectively camouflaged, way too small to be noticed, or are slightly submerged under the surface, which renders them virtually invisible to the naked eye.

On one particular dive, we were anchored close to a lighthouse upon a rock outcropping that served as a resting place for about 20 sea lions. The water surface showed a slight chop due to the wind, so it was difficult to visualize anything translucent on the surface. I donned my full wet suit, buoyancy compensator, and mask, but did not "smear up" with Safe Sea for this water entry, so my hands, neck, and face were exposed. and jumped feet first off the boat into the water. Someone then handed me my underwater camera, and I kicked gently to the anchor line to meet up with the other divers. In a flash, I experienced incredibly intense burning pain over both of my hands and wrists. The top of my left hand was on fire, while the underside of my right wrist hurt as if it had suddenly been lanced with 1000 needles. I stuck my facemask in the water and saw the purple "sails" of two small Portuguese man-of-war "jellyfish" (colonial siphonophores actually, but that's not critical to the discussion), with long trailing dark tentacles that terminated in their attachment to my body. The tentacles stuck to my skin like the webs emitted by Spiderman, so I shook my hands and forearms as hard as I could to pull them loose, to no avail.

I held my camera in my left hand, and while shaking it, the muscles in my hand and wrist went into a brief intense spasm from the sting, so I dropped the camera, which spiraled down into the depths below me. Fortunately, it came to rest in clear view 60 feet below me. Another diver thoughtfully dove down and retrieved it. Meanwhile, the friend of my son, who was diving with us, caught a tentacle across the throat, and was stunned and frightened. He exited the water and went back up on the boat to sit out the dive. I didn't see or hear him become injured, so I had no idea that he had been stung or was now suffering back on deck.

I pulled and rubbed the tentacles off my hands while I was in the ocean, waited a few moments, decided that I could tolerate the pain, and continued my dive. While I was underwater, my son's friend attempted to treat his sting by rubbing it with an ice cube, which is not the correct thing to do. When I ended my dive and returned to the boat, I learned of his sting, and treated him with an effective therapy - application of a mixture of rubbing alcohol and vinegar to the skin, which immediately ended the stinging pain.

Shame on me for not using Safe Sea before I entered the water. Had I followed my own advice, I would either have not been stung or had a much less severe reaction to the man-of-war. I've warned so many thousands of people of the hazards of getting stung that you would think I'd be a bit smarter. I can assure you that from this point forward, I won't be diving without taking proper precautions. Four days after the original sting, the skin reaction resembled a bad poison oak rash, with red, raised, and itchy bumps that perfectly define the attachment of the tentacles to my skin. It required a full four weeks for the rash to resolve.

I hope that none of you ever has the need for the following advice, but just in case you are in the ocean and are stung by a Portuguese man-of-war, jellyfish, or other similar stinging creature, here is what you should do:

1. Exit the water if possible.
2. Immediately rinse the wound with seawater, not with freshwater. Do not rub the wound with a towel or clothing to remove adherent tentacles. Nonforceful freshwater rinsing or a rubbing variety of abrasion is felt to stimulate any microscopic stinging cells that have not already fired. Surf life savers (lifeguards) in the United States and Hawaii have reported that a freshwater hot shower applied with a forceful stream may decrease the pain of an sting.
3. Remove any visible tentacles with forceps or a well gloved hand. In an emergency, the palm of the hand is relatively protected, but take care not to become stung.
4. Commercial (chemical) cold or ice packs applied over a thin dry cloth or plastic bag have been shown to be effective when applied to mild or moderate stings. Whether the melt water from ice applied directly to the skin can stimulate the discharge of stinging cells has not been determined.
5. Acetic acid 5% (vinegar) is the treatment of choice to inactivate most jellyfish toxins. The vinegar should be applied continuously for at least 30 minutes or until the pain is relieved. This may be done by soaking a napkin or cloth and placing it on the affected skin.
6. Different species respond better or worse to different topical decontaminants. There are substances that may be more specific and therefore more effective. Depending on the species, these include isopropyl (rubbing) alcohol (40% to 70%), dilute ammonium hydroxide, sodium bicarbonate (baking soda), lemon or lime juice, olive oil, sugar, urine, and papain (papaya latex [juice] or unseasoned meat tenderizer powdered or in solution).
7. Perfume, aftershave lotion, and high proof liquor are not particularly useful and may be detrimental. Other substances mentioned to be effective at one time or another, but which are to be condemned on the basis of toxicity, are organic solvents such as formalin, ether, and gasoline.

Immersing the area in hot water has generally not been recommended, on the premise that the fresh water solution causes stinging cells to discharge. However, one study compared hot (40 to 41 degrees Centigrade [104 to 105.8 degrees Fahrenheit]) water immersion to papain meat tenderizer or vinegar for treatment of a single-tentacle Carybdea alata (Hawaiian box) jellyfish sting to the forearm, and found the hot water immersion to be the most beneficial.

Once the wound has been soaked with a decontaminant (e.g., vinegar), remaining (and often “invisible”) stinging cells must be removed. The easiest way to do this is to apply shaving cream or a paste of baking soda, flour, or talc and to shave the area with a razor or similar tool. If sophisticated facilities are not available, the stinging cells should be removed by making a sand or mud paste with seawater and using this to help scrape the victim’s skin with a sharp edged shell or piece of wood. The rescuer must take care not to become stung; bare hands must be rinsed frequently.

Tags: Portuguese man-of-war, jellyfish, marine sting, medical, physician, health, wilderness medicine, outdoor medicine, healthline

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