The lionfish (Pterois volitans) belongs to the group of venomous Scorpaenidae and their natural habitat is restricted to the tropical regions of the world, primarily the Caribbean Sea and Central America [1]. However, studies have confirmed their presence throughout the Atlantic Ocean, resulting in the increased risk for lionfish stings in South America and the United States, in addition to the Caribbean countries [2]. Lionfish sting is considered to be a rare occurrence in clinical practice and activities that increase the risk include fishing, diving, or swimming in the mentioned areas [1] [2]. Some reports have documented stings from lionfish kept in aquariums as well [3]. The pathogenesis of a lionfish sting stems from the neurotoxic venom that is released by the fish during direct contact [4]. Patients almost always present with symptoms involving a single extremity (upper much more commonly than lower) [2] [5], and most common signs are erythema and extensive edema accompanied by pain that is described as quite severe, whereas paresthesias, abdominal cramping, local heat, cyanosis, and blistering of the skin are frequent findings as well [1] [2] [4] [5]. Cardiovascular symptoms, such as hypotension and tachycardia, are seen in a subset of patients, while hyperthermia, development of a localized infection, and transient weakness are less common findings [2] [4] [5] Although the clinical course typically ends with a good recovery without significant sequelae, limb paralysis, anaphylaxis, and heart failure have been reported [2] [4] [5].

• Subcutaneous Bleeding

  They also may result in rapid edema (swelling caused by fluid retention) and subcutaneous bleeding. Swelling typically clears in two-to-three days, while the tissue discolorations can last up to five days. [scubadiving.com]

• Severe Pain

  Not only do treatment facilities have access to some really nifty pain medications that you WILL want, there can be other complications that aren’t immediately apparent, too: Severe pain can cause shock which may involves shortness of breath, weakness [lionfish.co]

  Signs and symptoms Severe pain Redness, bruising, swelling Treatment Prevention is the best treatment. Stay aware of your surroundings and remember lionfish can sting after they are dead. [tdisdi.com]

  The venom is composed of acetylcholine and a neurotoxin which causes severe pain, swelling and rash in humans. Tim Codling, avid diver and lionfish culler was recently stung while removing a lion fish from the cobalt blue waters of Grand Cayman. [idivecayman.com]

  Following envenoming the affected individual presents with Immediate severe pain at the sting site Local swelling, bruising and puncture marks. [lifeinthefastlane.com]

  The primary symptom of stonefish envenomation is burning, severe pain, which soon begins to spread up the limb. In addition, serious swelling begins shortly after the sting. [dengarden.com]

• Localized Pain

  In a series of 101 documented cases of captive lionfish envenomations in the US, the following effects were reported (Gallagher, 2001): 92% of patients experienced local pain 60% of patients experienced edema 13% of patients experienced systematic symptoms [reefkeeping.com]

  Judging from this and other reports in the United States, the vast majority of lionfish stings appear to result in uncomplicated wounds with severe local pain that is responsive to immersion therapy. [emedicine.medscape.com]

  For example, in a series of 101 documented cases of captive lionfish envenomations here in the United States, the following effects were reported by Gallagher (2001): 92 percent of patients experienced local pain, 60 percent of patients experienced swelling [tfhmagazine.com]

  Victims of Irukandji Syndrome experience a reaction to the venom that is much worse than localized pain originating at the site of the sting. [dengarden.com]

• Localized Edema

  Lionfish sting is notable for its severe clinical presentation in the form of erythema, paresthesias, profound localized edema, and abdominal cramping. Systemic symptoms are rare. [symptoma.com]

• Hyperthermia

  Cardiovascular symptoms, such as hypotension and tachycardia, are seen in a subset of patients, while hyperthermia, development of a localized infection, and transient weakness are less common findings Although the clinical course typically ends with [symptoma.com]

• Sighing

  Okay, so, (sighs). First, most important thing. Hot water, gotta get hot water on my hand as soon as possible. Gotta heat it up. I'll sit down here. Wow. You all right? That is some radiating pain. [read-videos.com]

• Overeating

  Anyway it is over now,but i am tellin' you it was one of those pains that was so bad I couldn't even pinpoint the pain.Glad that is over. Lionfish stings are bad. I got kniked by one of them before it was a little sting but felt really bad. [reef2reef.com]

  Signs that others will see besides you sweating are that blood may be coming out of the wound and over time the area that was stung will swell up. [lionfish-hunting.com]

  Over increasingly painful minutes, I surface and hand up my gear. [turtlebaydiveresort.com]

  If hot water is not immediately available on the boat, exhaust water from an engine can be used as well as hot compresses over the area. Click here to see the portable heating devices that are available for treating lionfish stings. [lionfishhunting.com]

  Undercurrent subscriber Carol Cox (Mexico Beach, FL) has been dealing with this over the summer. Here is her story (which doesn't have an official final ending until she is paid in full by DAN and her insurance company). [undercurrent.org]

• Nausea

  In worst case scenarios the symptoms may include headache, nausea, abdominal pain, delirium, seizures, paralysis of limbs, changes in blood pressure, breathing difficulties, heart failure and tremors, pulmonary edema, and loss of consciousness. [hawaiiscubaadventures.com]

  Colliding with a lionfish's toxic sting is likely to cause nausea and vomiting. You may feel feverish with headaches and dizziness. It is also common to suffer breathing difficulties from lionfish stings. [private-scuba.com]

  […] bruising Bleeding and edema, formation of blister Swelling of the wound Sweating Headaches Abnormal heart rate, reduced blood pressure Allergic shock or reaction, in some cases Shortness of breath; breathing difficulties Muscle cramps, abdominal cramps Nausea [dovemed.com]

  Redness, bruising, swelling, numbness, tingling, and tissue shedding at the wound site Severe reactions include: Nausea Vomiting Abdominal cramps Tremors Abnormal heart rhythms Weakness Shortness of breath Seizures Decreased blood pressure Fainting Paralysis [webmd.com]

  On rare occasions, when the venom spreads to other parts of the body, people may experience headaches, chills, cramps, nausea, and even paralysis and seizures. [oceanservice.noaa.gov]

• Vomiting

  If the injured person appears intoxicated or is weak, vomiting, short of breath or unconscious, seek immediate advanced medical care. [blog.daneurope.org]

  Colliding with a lionfish's toxic sting is likely to cause nausea and vomiting. You may feel feverish with headaches and dizziness. It is also common to suffer breathing difficulties from lionfish stings. [private-scuba.com]

  In humans, lionfish venom can cause systemic effects such as vomiting, fever and sweating. In some cases, it has been lethal. The effect of the venom weakens the force of muscular contractions), and increases the heart rate. [turtlebaydiveresort.com]

  Bleeding and edema, formation of blister Swelling of the wound Sweating Headaches Abnormal heart rate, reduced blood pressure Allergic shock or reaction, in some cases Shortness of breath; breathing difficulties Muscle cramps, abdominal cramps Nausea, vomiting [dovemed.com]

  Redness, bruising, swelling, numbness, tingling, and tissue shedding at the wound site Severe reactions include: Nausea Vomiting Abdominal cramps Tremors Abnormal heart rhythms Weakness Shortness of breath Seizures Decreased blood pressure Fainting Paralysis [webmd.com]

• Abdominal Cramps

  Lionfish sting is notable for its severe clinical presentation in the form of erythema, paresthesias, profound localized edema, and abdominal cramping. Systemic symptoms are rare. [symptoma.com]

  Redness, bruising, swelling, numbness, tingling, and tissue shedding at the wound site Severe reactions include: Nausea Vomiting Abdominal cramps Tremors Abnormal heart rhythms Weakness Shortness of breath Seizures Decreased blood pressure Fainting Paralysis [webmd.com]

  Severe reactions include nausea, vomiting, abdominal cramps, tremors, abnormal heart rhythms, weakness, headache, diarrhea, slow heart rate (bradycardia), shortness of breath, seizures, decreased blood pressure, fainting, and paralysis. [emedicinehealth.com]

• Abdominal Pain

  In worst case scenarios the symptoms may include headache, nausea, abdominal pain, delirium, seizures, paralysis of limbs, changes in blood pressure, breathing difficulties, heart failure and tremors, pulmonary edema, and loss of consciousness. [hawaiiscubaadventures.com]

  Worst case scenarios, though not normally fatal to humans, include headache, nausea, abdominal pain, delirium, seizures, paralysis of limbs, changes in blood pressure, breathing difficulties, heart failure and tremours, pulmonary edema, and loss of consciousness [dive-the-world.com]

• Cyanosis

  […] present with symptoms involving a single extremity (upper much more commonly than lower), and most common signs are erythema and extensive edema accompanied by pain that is described as quite severe, whereas paresthesias, abdominal cramping, local heat, cyanosis [symptoma.com]

  Cardiovascular signs such as hypotension, bradycardia, collapse, pulmonary oedema and cyanosis are rarely reported. Differential diagnosis Other fish stings Stingray injury. [lifeinthefastlane.com]

• Skin Ulcer

  The complications that may arise from a Lionfish Sting may include: Bleeding and skin ulceration can cause secondary bacterial or fungal infections to develop Tissue necrosis at the site of the sting Anaphylaxis type allergic reaction Respiratory distress [dovemed.com]

• Ulcer

  The complications that may arise from a Lionfish Sting may include: Bleeding and skin ulceration can cause secondary bacterial or fungal infections to develop Tissue necrosis at the site of the sting Anaphylaxis type allergic reaction Respiratory distress [dovemed.com]

• Myalgia

  […] infusion Give oxygen, IV fluids and administer IM adrenaline 0.01 mg/kg(max 0.5 mg) to lateral thigh Serum sickness This relatively benign and self limiting complication may occur 5–10 days after antivenom Manifestations include fever, rash, arthralgia and myalgia [lifeinthefastlane.com]

• Fidgeting

  The discomfort causes me to shift and fidget. The intense pain lasts for another few hours, and ultimately subsides to a dull throb. It takes me a week to get over the sensitivity in the region. [turtlebaydiveresort.com]

• Sciatica

  NEWS-PRESS.COM Published 12:09 AM EDT Aug 15, 2014 Question: What feels like a combination of the worst trip ever to the dentist, a ruptured ear drum, a dislocated shoulder, a severe burn, a nail through the kneecap, an electrical shock, a bad case of sciatica [news-press.com]

• Numbness of the Hand

  I sucked it up and the intense pain went away after about an hour however a slight numbness in my hand continued for 2 full days after the sting. I have whacked several dozen of these little buggers and have given seminars on how to handle them. [scubaboard.com]

Because of the fact that lionfish stings are rather easily treated by immersing the affected extremity in hot water (due to the heat-labile properties of the neurotoxin) [4] [5], early recognition of this clinical entity can lead to prompt and effective therapy. For this reason, the physician's role in obtaining a detailed patient history is vital. Previous activities and confirmation of a lionfish sting by the patient is perhaps the most important piece of information needed to make the diagnosis. A full physical examination should follow, during which a complete inspection, as well as palpation of the affected extremity, must be carried out. At the time of admission, lionfish stings may present as erythema, blistering, or dermal necrosis [1] [6], depending on the duration of symptoms before the examination. Moreover, typical symptoms can be completely absent in the case of an "empty sting", ie. no venom was released from the lionfish [3]. Although isolated reports document several abnormalities during biochemical workup in a small number of patients (hypophosphatemia, elevated liver enzymes, thrombocytopenia) [5], the diagnosis primarily rests on clinical criteria supported by findings revealed during history.

1. Hobday D, Chadha P, Din AH, Geh J. Denaturing the Lionfish. Eplasty. 2016;16:ic20.
2. Resiere D, Cerland L, De Haro L, et al. Envenomation by the invasive Pterois volitans species (lionfish) in the French West Indies—a two year prospective study in Martinique. Clin Toxicol (Phila) 2016;9:1–6.
3. Haddad V, Stolf HO, Risk JY, Franca FOS, Cardoso JLC. Report of 15 injuries caused by lionfish (Pterois volitans) in aquarists in Brazil: a critical assessment of the severity of envenomations. J Venom Anim Toxins Incl Trop Dis. 2015;21:8.
4. Satora L. Lionfish envenomations in Poland. Przegl Lek. 2009;66(6):285-286.
5. Diaz JH. Marine Scorpaenidae Envenomation in Travelers: Epidemiology, Management, and Prevention. J Travel Med. 2015;22(4):251-258.
6. Patel MR, Wells S. Lionfish envenomation of the hand. J Hand Surg Am. 1993;18:523 – 525.