Jellyfish are found in every ocean and are prevalent in the tropics and northern Europe [1] [2] [3] [4] [5]. Of nearly 9000 species, only around 100 cause harm to humans [1] [2]. Specifically, Physalia physalis [5], Chironex fleckeri [6], and Carukia barnesi are the three most toxic species. Jellyfish sting is a frequent event as it has been reported that 150 million incidents occur annually [7]. There are as many as 800 incidents in some Pacific locations daily [8]. Fortunately, most jellyfish stings result in recovery.

Depending on the type of species and the envenomation dose [9], effects can range from mild symptoms to rapid fatality [10] [11] [12]. Local symptoms and signs include pain, swelling, pruritus, and eventually necrosis at the site of an injection [1] [10] [13]. Purplish-brownish vesicles develop and may last anywhere from minutes to weeks.

Systemic findings, if present, include nausea, emesis, fever, malaise, headache, paresthesias, and muscular spasms [14] [15]. Multiorgan effects reflect the involvement of gastrointestinal, cardiovascular, hematologic, neurologic, urinary, musculoskeletal, immunologic, and/or pulmonary systems [10] [16]. Additionally, ophthalmologic manifestations can include conditions such as ulceration of the cornea, conjunctivitis, and swelling of the eyelids.

While the majority of cases are nontoxic, some lead to sequelae such as infection of the wound, acute kidney failure, hemolysis, rhabdomyolysis, pulmonary edema and respiratory distress, dangerous arrhythmias, and cardiopulmonary arrest [14] [15] [16] [17].

Chronic effects include dermatologic features such as the development of keloids and granulomas and changes in pigmentation.

Vital signs changes may include tachycardia and alteration in blood pressure [14] [15]. Furthermore, the sting site is characterized by tenderness, erythema, and edema [6]. The color change and scarring may be permanent [16].

• Severe Pain

  Even mild stings cause severe pain and can leave horrible scars. Cape York, Queensland, Australia, is home to many Australian box jellyfish. [hawaii.edu]

  Always seek emergency medical care if you are stung by a jellyfish on the face, mouth, eyes, or genital area or if you become severely ill, have difficulty breathing or swallowing, or develop severe pain following the sting. [medicinenet.com]

  He experienced severe pain in his right eye, requiring narcotic analgesia, and had decreased visual acuity associated with right-sided facial swelling. [ncbi.nlm.nih.gov]

  The sting causes pain or burning at the site. Sometimes hives in the sting area occur. Blisters can occur in severe cases. Severe pain lasts 1-2 hours. Itch may last for a week. If the skin damage is severe, red or purple lines can last for weeks. [kidsclinic.pediatricweb.com]

• Inflammation

  Paracetamol and ibuprofen can also be taken to help relieve pain and inflammation. [dailymail.co.uk]

  It is possible for an allergic reaction to occur that further increases the inflammation and severity of the rash. [medicinenet.com]

  The porins tear holes in blood cells and trigger an inflammation response in mast cells (cells in the immune system responsible for allergies and anaphylaxis). Some proteins in the venom cause local pain and skin lesions. [zmescience.com]

  After 5 asymptomatic weeks, she developed unilateral orbital inflammation that did not respond to systemic antibiotics, antihistamines, or steroids. Imaging revealed a rapidly growing mass of the right lacrimal gland. [ncbi.nlm.nih.gov]

• Fever

  Systemic findings, if present, include nausea, emesis, fever, malaise, headache, paresthesias, and muscular spasms. [symptoma.com]

  You may have a fever, weakness, or joint stiffness or swelling. Medical treatment may ease the discomfort and prevent complications from a delayed reaction. [healthlinkbc.ca]

  Certain patients can also develop a fever or begin to sweat profusely. Patients who develop any of these jellyfish side effects should be taken to an emergency medical care clinic or hospital as soon as possible. [livestrong.com]

• Dyspnea

  In some cases, depending on the sensitivity of the person and the species of jellyfish, severe localized pain and nausea, weakness, excessive lacrimation, nasal discharge, muscle spasm, perspiration, difficulty in swallowing, and dyspnea may occur. [medical-dictionary.thefreedictionary.com]

• Vomiting

  Nausea or Vomiting Patients stung by a jellyfish can experience stomach upset side effects within minutes of injury. These stomach-related side effects can include nausea or vomiting, which may occur in conjunction with diarrhea. [livestrong.com]

  Other symptoms include: Paraesthesia (tingling and prickling) and itching Red bumps and patches, often in a ladder-like pattern Swelling Sweating in affected area (irukandji) Nausea and vomiting Muscle pain and cramps. [dermnetnz.org]

  Seek medical care if the person is having difficulty breathing, is bleeding profusely, or other body-wide (generalized) symptoms are occurring, such as the following: Nausea or vomiting Paralysis Sweating Weakness Cramps Diarrhea There is pain in an [skinsight.com]

  […] a cold pack do not touch any spines with your bare hands do not cover or close the wound Go to A&E or call 999 if you have been stung and have: difficulty breathing chest pain fits or seizures severe swelling around the affected area severe bleeding vomiting [nhs.uk]

• Nausea

  Nausea or Vomiting Patients stung by a jellyfish can experience stomach upset side effects within minutes of injury. These stomach-related side effects can include nausea or vomiting, which may occur in conjunction with diarrhea. [livestrong.com]

  Other symptoms include: Paraesthesia (tingling and prickling) and itching Red bumps and patches, often in a ladder-like pattern Swelling Sweating in affected area (irukandji) Nausea and vomiting Muscle pain and cramps. [dermnetnz.org]

  Seek medical care if the person is having difficulty breathing, is bleeding profusely, or other body-wide (generalized) symptoms are occurring, such as the following: Nausea or vomiting Paralysis Sweating Weakness Cramps Diarrhea There is pain in an [skinsight.com]

  In some cases, depending on the sensitivity of the person and the species of jellyfish, severe localized pain and nausea, weakness, excessive lacrimation, nasal discharge, muscle spasm, perspiration, difficulty in swallowing, and dyspnea may occur. [medical-dictionary.thefreedictionary.com]

• Diarrhea

  Seek medical care if the person is having difficulty breathing, is bleeding profusely, or other body-wide (generalized) symptoms are occurring, such as the following: Nausea or vomiting Paralysis Sweating Weakness Cramps Diarrhea There is pain in an [skinsight.com]

  Coughing, wheezing, difficulty breathing, or a feeling of fullness in the mouth, throat, or neck Light-headedness, confusion, or agitation Headache, dizziness, or vertigo Nausea, vomiting, diarrhea, and stomach cramps Fever and chills Hives and flushing [healthlinkbc.ca]

  These stomach-related side effects can include nausea or vomiting, which may occur in conjunction with diarrhea. Certain patients can also develop a fever or begin to sweat profusely. [livestrong.com]

  The progressive effects of a jellyfish sting may include nausea, vomiting, diarrhea, lymph node swelling, abdominal pain, numbness/tingling, and muscle spasms. Severe reactions can cause difficulty breathing, coma, and death. [emedicinehealth.com]

• Abdominal Pain

  WASP OR BOX JELLYFISH Severe burning pain and sting site blistering Raised red spot where stung Skin tissue death Breathing difficulty Sweating Nausea and vomiting Abdominal pain Changes in pulse Chest pain Collapse Headache Muscle pain and muscle spasms [medlineplus.gov]

  When to see your doctor Call your doctor if you have been stung and have: increasing numbness or difficulty breathing signs of poisoning: abdominal pain, muscle cramps, nausea, vomiting signs of infection later: increasing pain, redness, swelling, red [health.govt.nz]

  Symptoms include an intense, stinging pain, itching, rash, and raised welts. The progressive effects of a jellyfish sting may include nausea, vomiting, diarrhea, lymph node swelling, abdominal pain, numbness/tingling, and muscle spasms. [emedicinehealth.com]

• Chest Pain

  WASP OR BOX JELLYFISH Severe burning pain and sting site blistering Raised red spot where stung Skin tissue death Breathing difficulty Sweating Nausea and vomiting Abdominal pain Changes in pulse Chest pain Collapse Headache Muscle pain and muscle spasms [medlineplus.gov]

  Certain patients may also experience chest pain in conjunction with these side effects. These patients require immediate emergency medical care to prevent further medical complications. [livestrong.com]

  WHAT TO DO IF YOU ARE STUNG BY A JELLYFISH If the person stung doesn't have serious symptoms such as breathing difficulties or chest pain and hasn't been caught in a sensitive area, such as the face or genitals you can deal with a sting yourself, says [dailymail.co.uk]

• Cyanosis

  We report a case of digital ischaemia in a 31-year-old man who presented with sudden hand numbness, swelling, and cyanosis 4 days after a jellyfish sting. [ncbi.nlm.nih.gov]

• Muscle Cramp

  Symptoms of stings from different types of jellyfish are: LION'S MANE Breathing difficulty Muscle cramps Skin burning and blistering (severe) PORTUGUESE MAN-OF-WAR Abdominal pain Changes in pulse Chest pain Chills Collapse Headache Muscle pain and muscle [medlineplus.gov]

  Muscle Cramps A jellyfish sting can cause side effects of muscle cramping in affected patients, according to Medline Plus, a medical information website supported by the National Institutes of Health. [livestrong.com]

  Muscle spasm, muscle cramps, joint pain, or generalized aching Credits By Healthwise Staff Primary Medical Reviewer William H. [healthlinkbc.ca]

• Lacrimation

  Imaging revealed a rapidly growing mass of the right lacrimal gland. Urgent anterior orbitotomy was performed and the lacrimal gland was biopsied. [ncbi.nlm.nih.gov]

  In some cases, depending on the sensitivity of the person and the species of jellyfish, severe localized pain and nausea, weakness, excessive lacrimation, nasal discharge, muscle spasm, perspiration, difficulty in swallowing, and dyspnea may occur. [medical-dictionary.thefreedictionary.com]

• Foreign Body Sensation

  Following debridement of the traumatized areas, the corneal epithelium healed completely in 24 hours, resulting in increased visual acuity and decreased foreign body sensation. [ncbi.nlm.nih.gov]

• Skin Rash

  Skin Rash After being stung by a jelly fish, patients can develop a red, irritated skin rash at the site of the sting. A sting from a sea nettle generally results in mild skin-rash symptoms. [livestrong.com]

  […] irritation or rashes that last for weeks. [medlineplus.gov]

  Picture of a Typical jellyfish sting Jellyfish Sting Sign Rash Rash is a general, nonspecific term that describes any visible skin outbreak. [emedicinehealth.com]

• Eruptions

  Sea bather's eruption What actually causes sea bather's eruption ? Sea bather's eruption is a hypersensitivity reaction to the larval form, or planulae, of the thimble jellyfish, Linuche unguiculata. [dermnetnz.org]

  A 7-year-old boy, taking lessons at a yacht school at Enoshima in Kanagawa prefecture in Japan, recognized a linear eruption on his left lower leg during practice in August 2012. As it gradually enlarged, he visited a local medical clinic. [ncbi.nlm.nih.gov]

  On day 6, vesicular lesions erupted from the site of envenomation (Panel B) and progressed rapidly over the next 24 hours (Panel C), prompting treatment with a 1-week course of glucocorticoids, antihistamines, and antibiotics. [nejm.org]

• Dermatitis

  Based on the clinical course, clinical features, and laboratory findings, the lesion was considered to be delayed flare-up allergic dermatitis caused by a jellyfish sting [1]. [ncbi.nlm.nih.gov]

  Sea bather's rash can also look very similar to seaweed dermatitis, but no seaweed is found on the skin or in swimwear. See smartphone apps to check your skin. [dermnetnz.org]

  The sea anemone Phyllodiscus semoni (night or wasp-sea anemone) located in the Western Pacific Ocean is reported to cause fulminant dermatitis and acute renal failure in humans Corals are important components of living reefs. [emedicine.medscape.com]

• Eczema

  Considering eczema, topical steroid treatment and occlusive dressing technique were started but the nodule remained. [ncbi.nlm.nih.gov]

  […] as benzocaine cleanse ulcerated wounds several times a day and keep covered with antibiotic ointment Other treatments systemic antibiotics for wound infections tetanus booster if status unknown or lapsed corticosteroids and antihistamines for delayed eczema-type [drhull.com]

  Hydrocortisone eczema cream. • if muscle spasms persist see a doctor. [bugbog.com]

• Erythema

  Erythema and pain were assessed at 15-minute intervals over a 2-hour period. RESULTS: In the C. fuscescens group, all 12 arms pretreated with conventional sunscreen demonstrated erythema, and all subjects noted subjective discomfort. [ncbi.nlm.nih.gov]

  Outcomes measured will include pain and erythema. [clinicaltrials.gov]

  Furthermore, the sting site is characterized by tenderness, erythema, and edema. The color change and scarring may be permanent. A detailed history should be elicited from the patients and/or witnesses if possible. [symptoma.com]

  Clinical features include intense local pain and dermal erythema. Hot water immersion provides safe symptomatic relief. Unlike Physalia stings in other parts of the world, major systemic envenoming does not occur. [lifeinthefastlane.com]

• Headache

  Symptoms of stings from different types of jellyfish are: LION'S MANE Breathing difficulty Muscle cramps Skin burning and blistering (severe) PORTUGUESE MAN-OF-WAR Abdominal pain Changes in pulse Chest pain Chills Collapse Headache Muscle pain and muscle [medlineplus.gov]

  Symptoms (as little as 5 minutes after apparently mild stings) • lower back pain, intense headache. • muscle cramps and shooting pains, nausea, vomiting. • catastrophically high blood pressure. • restlessness and feeling of impending doom. • death from [bugbog.com]

  […] medical provider right away if any of the following is noticed: The sting site is anywhere on the face or genitals or covers a large part of the body Symptoms remain the same or worsen Severe allergic reaction Nausea or vomiting Weakness Muscle spasms Headaches [goaskalice.columbia.edu]

• Burning Sensation

  If you get hit by sea lice, it’s usually no more than a temporary mild itch or burning sensation that goes away as quickly as you feel it. On rare occasions, the sting of sea lice is delayed and can be rather painful and uncomfortable for days. [keywestaquarium.com]

  This toxin results in a burning sensation and reddened skin. A study led by researchers at Stanford University compared sunscreen to a cream made in Israel called Safe Sea. [faculty.washington.edu]

  This will help decrease the burning sensation from the sting. It may also help to take a hot shower as soon as possible. A recent study concluded that jellyfish stings are treated more effectively by hot water than by ice packs. [healthline.com]

  Symptoms include high blood pressure, vomiting, headaches, extreme cramping and pain, and a burning sensation. Irukadji syndrome can last up to two weeks, and there's no antidote. [animals.howstuffworks.com]

• Seizure

  […] ibuprofen do not use vinegar do not pee on the sting do not apply ice or a cold pack do not touch any spines with your bare hands do not cover or close the wound Go to A&E or call 999 if you have been stung and have: difficulty breathing chest pain fits or seizures [nhs.uk]

• Agitation

  Jellyfish nematocysts release venom when under pressure; therefore, attempting to scrape them off further agitates the situation and encourages for poison to enter the body. [pastemagazine.com]

  Coughing, wheezing, difficulty breathing, or a feeling of fullness in the mouth, throat, or neck Light-headedness, confusion, or agitation Headache, dizziness, or vertigo Nausea, vomiting, diarrhea, and stomach cramps Fever and chills Hives and flushing [healthlinkbc.ca]

A detailed history should be elicited from the patients and/or witnesses if possible. The key questions should consist of details about the time of the sting, the onset and evolvement of the clinical features, the location of the incident, and identity of the organism. Very importantly, a physical exam must be performed and the patient should be immediately evaluated for the basic life support as well as for the evidence of local and systemic effects [10]. Additionally, the clinician should eliminate the tentacles as much as possible [1] [18]. Note that patients with anaphylaxis should be managed urgently and resuscitated promptly. Pain and wound care are also important to treat.

Individuals with severe manifestations should be assessed for organ damage with a complete blood count (CBC), complete metabolic panel (CMP) including renal and liver function tests, cardiac enzymes, thyroid function tests, and creatine phosphokinase. Additionally, urinalysis and arterial blood gases (ABG) should be performed.

Chest radiography is indicated for patients with respiratory distress.

Electrocardiogram (ECG) is useful for identifying arrhythmias. Finally, skin samples can be evaluated for the presence of nematocysts.

Their studies showed that nearly all of these treatments were useless at best and harmful at worst. [azula.com]

But - you're in for a shock - that particular treatment only makes the sting worse. The real cure may involve a dash to nearest chip van. [bbc.com]

The Portuguese man o’ war The traditional first-aid treatment for jellyfish stings is all washed up and could actually cause more harm than good, a ground-breaking new study from NUI Galway reveals. [independent.ie]

Treatment should be directed at removing as many visible spines as possible. Waxing and stripping the area may help remove residual spines. Ammonia solution can dissolve small spine fragments. [dermnetnz.org]

The most and least effective treatments The team found that some of the most commonly recommended actions, including rinsing with seawater, scraping the tentacles and applying ice, dramatically increased the severity of the stings. [hawaii.edu]

Cubozoan envenomations: clinical features, pathophysiology and management. In: Goffredo S, Dubinsky EZ, eds. The Cnidaria, Past, Present and Future: The World of Medusa and Her Sisters. Switzerland. Springer; 2016:637-652. Updated by: Jacob L. [medlineplus.gov]

A Hawaii-based company has recently developed treatments to provide pain relief and even prevention for jellyfish stings. [zmescience.com]

Instead of rinsing with seawater or scraping, the team found that rinsing with vinegar—which irreversibly prevents the stinging cells from firing—or even simply plucking tentacles off with tweezers led to less venom injection. [hawaii.edu]

The tubule follows the needle, and poison is injected into the body Keep ocean lovers in the water and out of agony with Nidaria lotion to prevent jellyfish stings How Nidaria Lotion Works Nidaria products protect against jellyfish stings in several ways [nidaria.com]

Water safety campaigns should incorporate information on the prevention and early treatment of such stings. [ncbi.nlm.nih.gov]

This is important to do in order to prevent further release of the jellyfish's toxin. To help accomplish this, thoroughly rinse the affected region with vinegar (preferably) or seawater. [goaskalice.columbia.edu]

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