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].

• 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]

  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]

  Large venom symptoms are vomiting, dizziness, weakness and headache. Anaphylaxis (A severe allergic reaction). Life-threatening reactions are very rare with the stings. Most are caused by box jellyfish found in the South Pacific and Australia. [kidsclinic.pediatricweb.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]

  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]

  With severe stings — when a lot of venom is injected into the skin or when a person is extremely allergic to the venom — weakness, dizziness, nausea, headache, muscle aches, spasms and difficulty breathing can result. [chop.edu]

• 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 [nlm.nih.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

  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]

  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 [nlm.nih.gov]

  pain fits or seizures severe swelling around the affected area severe bleeding vomiting lightheadedness or loss of consciousness Find your nearest A&E department Symptoms of sea creature stings The main symptoms of sea creature stings are intense pain [nhs.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]

• 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]

• 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]

• Muscle Cramp

  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]

  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 [nlm.nih.gov]

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

• Headache

  With severe stings — when a lot of venom is injected into the skin or when a person is extremely allergic to the venom — weakness, dizziness, nausea, headache, muscle aches, spasms and difficulty breathing can result. [chop.edu]

  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]

  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 [nlm.nih.gov]

• 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]

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.

The investigators would like to investigate which treatment is best out of some of the more commonly studied treatments for reducing pain and erythema. [clinicaltrials.gov]

Treatment Treatment for jellyfish includes first-aid care and medical treatment, depending on the type of jellyfish, the severity of the sting and your reaction to it. [mayoclinic.org]

Further treatment after showering, etc. is useful too. The bottle provides enough solution for multiple treatments. We had two occurances during the week and still had half a bottle remaining. May 15, 2016 Verified Purchase Good stuff. [amazon.com]

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

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. [nlm.nih.gov]

And while it prevents further nematocyst discharge, vinegar doesn't provide any pain relief from already injected venom. [dailymail.co.uk]

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

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]

In order to prevent themselves from perishing due to lack of food or being easily captured by a predator, they are equipped with thousands of special stinging cells called cnidocytes along their tentacles. [scienceabc.com]

But when a deep sore develops, you may need medical treatment to help the sore heal and prevent infection. Credits By Healthwise Staff Primary Medical Reviewer William H. [healthlinkbc.ca]

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