Coral Snake Toxicity

What is Coral Snake Toxicity?

Coral snakes belong to the Elapidae family and there are 40 to 50 species found in the Americas. In the US, three types are most common:

1. Eastern Coral Snake (Micrurus fulvius) – mainly found in Florida and the southeast US.
2. Texas Coral Snake (Micrurus tener) – mainly found in Texas and Northwestern Mexico.
3. Sonoran Coral Snake (Micruroides euryxanthus) – mainly found in Southeastern US and the state of Sonora in Mexico.

North American Coral snakes, found to the north of Mexico City, are known for their colourful bands of red, yellow, and black that wrap around their bodies. This pattern is different from the non-venomous shovel-nosed snake, which doesn’t have these circular bands. This colour arrangement can also help you tell apart a venomous coral snake from non-venomous ones like the king snake, which has a “red on black” pattern. An easy rule to remember is “red on yellow, kills a fellow; red on black, venom lack.”

Being bitten by a coral snake is rare compared to bites from pit vipers. However, their venom is very potent and can, after a delay, cause serious nerve damage and difficulty with breathing.

What Causes Coral Snake Toxicity?

Coral snakes like the M. fulvius and M. tener produce a venom that is a powerful nerve poison. Another species, the M. euryxanthus doesn’t usually cause severe symptoms in humans when it bites. Interestingly, it has a unique defensive sound feature called a “microfart,” which is caused by the release of air from its rear end.

Compared to pit viper snake bites, coral snake bites happen less frequently. This is mainly because coral snakes prefer to hide or escape from danger instead of facing it head-on. This means most coral snake bites happen when people intentionally touch or handle the snake, or when animals out of curiosity bother it.

Risk Factors and Frequency for Coral Snake Toxicity

Out of approximately 9,000 snake bites each year in the US, only between 25 to 50 are caused by coral snakes. The coral snakes that typically cause serious bites are the M. fulvius and M. tener species. In recent times, there has been just one recorded death in North America due to a bite from a coral snake.

Signs and Symptoms of Coral Snake Toxicity

If someone is bitten by a coral snake or their venom touches your skin, it’s important to note when this happened. The snake’s venom can cause severe health problems such as difficulty in breathing, but these might not appear until around 13 hours after the bite. If you can, try to confirm that the snake was a coral snake – taking a picture of it could be a good way to do this.

The person may initially experience a bit of pain at the spot of the bite (though there won’t always be visible marks), feel nauseous, start vomiting, get dizzy, and have stomach pain. The venom can also impact the ability to move, starting with facial muscle weakness such as drooping eyelids, difficulty speaking or swallowing, and then progressing to overall muscle weakness. One serious risk to watch out for is weakening of the breathing muscles, which could lead to respiratory problems. This is the most dangerous outcome of a coral snake bite, so these patients should be observed closely.

Take note of when the bite happened
Try to verify the snake’s identity
Initial symptoms may include mild pain, nausea, vomiting, dizziness, and stomach pain
Possible effects on muscle movement may include weakened facial muscles, difficulty speaking, difficulty swallowing, and overall muscular weakness
One major risk is respiratory problems, caused by the weakening of breathing muscles

Testing for Coral Snake Toxicity

When looking at potential coral snake bite victims, doctors would check for signs of neurological issues and trouble breathing. Regular lung function testing can help in noticing impending breathing difficulties. Symptoms like having less than 50% of standard lung capacity, low maximal inspiratory or expiratory pressures, indicate potential breathing issues.

Furthermore, changes in the mental state, monitoring carbon dioxide levels at the bedside, and measurements of blood gases can help track high carbon dioxide levels or respiratory acidosis, which may lead to respiratory failure. Muscle damage, specifically rhabdomyolysis, can be a result of M. fulvius coral snake bites, and should be assessed based on the situation. Unlike pit viper bites, coral snake bites do not often cause significant tissue decay around the bite area and blood clotting abnormalities.

Treatment Options for Coral Snake Toxicity

If someone is bitten by a snake, especially a coral snake, it’s important to protect them from further exposure to the snake, keep the wound clean, and limit movement to slow down the spread of the venom. It’s also recommended to calm the patient and make sure they get a tetanus shot. Bandages applied gently enough to allow blood flow but limit the flow of lymphatic fluid can help reduce how much venom enters the body.

Methods like using tourniquets, trying to suck out the venom, or applying ice are not advised. It’s also best to avoid any medications that could weaken muscles or impair lung function, as these could make it harder to monitor the patient for signs of venom’s effects on the nervous system.

All suspected coral snake bites need to be watched closely for at least 24 hours because the venom could cause life-threatening breathing problems that may take some time to develop. If the patient starts having trouble breathing, they might need to be intubated and treated with an antidote to coral snake venom or other drugs.

North American Coral Snake Antivenin (NACSA) is a standard antidote made from horse antibodies used to neutralize the venom of two types of North American coral snakes. It’s typically used at the first sign of breathing problems or neurological symptoms. However, its use for preventing symptoms in patients without any visible signs of venom effects is up for debate due to mixed results on clinical trials and the risk of allergic reactions.

If a coral snake bite is suspected, it’s recommended to contact the Poison Control Center or a toxicologist for advice on treatment. It’s important to note that the NACSA’s supply is limited because its production stopped in 2006 and any existing vials have expired, although the FDA extended its expiration date through 2019. If antidote treatment is needed, getting the required antivenom could take time and resources because it might not be readily available.

Before administering NACSA, it’s important to test if the patient has a reaction to the horse serum by giving a small amount first. If there are no allergic reactions, the recommended starting dose for both adults and kids is three to five vials administered gradually into a vein. There might be other antidotes that could work for coral snake bites, and a new antidote is currently being tested in clinical trials in the US.

Checking for signs of allergic reactions, like hives, difficulty breathing, low blood pressure, and swelling, is vital when a patient is receiving NACSA due to the risk of immediate and delayed hypersensitivity reactions. If an allergic reaction occurs, stop giving the antidote immediately and administer epinephrine, antihistamines, corticosteroids, and albuterol as needed based on the patient’s symptoms.

If the patient shows signs of venom affecting the nervous system or is having trouble breathing and there is no coral snake antivenom available, doctors might try a dose of anticholinesterase such as neostigmine. This medication increases the amount of a certain chemical at the junction of nerves and muscles, helping to restore neuromuscular transmission – but it should be given with an anticholinergic like atropine or glycopyrrolate to prevent potential excessive cholinergic effects. For optimal results, consult with a poison control center or a toxicologist for guidance.

When trying to figure out if someone has been exposed to snake venom, physicians have to consider other conditions that might present similar symptoms. These include:

Allergic reaction (anaphylaxis)
Blood clot in the vein (deep venous thrombosis)
Injury to the blood vessels in the arm or leg (extremity vascular trauma)
Scorpion sting (scorpion envenomation)
Severe infection (septic shock)
Reaction to a drug or antibiotic (serum sickness)
Wasp stings
Issues related to the care of a wound
Infections in a wound

It’s vital that doctors consider these possibilities and perform suitable tests to arrive at the correct diagnosis.

Frequently asked questions

Coral snake toxicity is the ability of coral snakes to produce venom that can cause serious nerve damage and difficulty with breathing.

Coral snake toxicity is relatively uncommon.

The signs and symptoms of Coral Snake Toxicity include: - Mild pain at the site of the bite (though there may not always be visible marks) - Nausea - Vomiting - Dizziness - Stomach pain - Weakened facial muscles, such as drooping eyelids - Difficulty speaking - Difficulty swallowing - Overall muscle weakness - Respiratory problems, caused by the weakening of breathing muscles It's important to note that these symptoms may not appear immediately and could take around 13 hours to manifest. If someone is bitten by a coral snake or their venom touches the skin, it's crucial to observe the timing of the incident and try to confirm the snake's identity. Taking a picture of the snake can be helpful in verifying its species.

Coral snake toxicity occurs when someone is bitten by a coral snake or when the venom from a coral snake touches the skin.

Allergic reaction (anaphylaxis), Blood clot in the vein (deep venous thrombosis), Injury to the blood vessels in the arm or leg (extremity vascular trauma), Scorpion sting (scorpion envenomation), Severe infection (septic shock), Reaction to a drug or antibiotic (serum sickness), Wasp stings, Issues related to the care of a wound, Infections in a wound.

The types of tests that a doctor would order to properly diagnose Coral Snake Toxicity include: - Regular lung function testing to assess breathing difficulties - Monitoring carbon dioxide levels at the bedside and measuring blood gases to track high carbon dioxide levels or respiratory acidosis - Assessing muscle damage, specifically rhabdomyolysis, based on the situation - Checking for signs of allergic reactions, such as hives, difficulty breathing, low blood pressure, and swelling, when administering the antidote (NACSA) - Testing for a reaction to the horse serum before administering NACSA - Consultation with a poison control center or toxicologist for guidance on treatment and potential alternative antidotes.

Coral Snake Toxicity is treated by protecting the patient from further exposure to the snake, keeping the wound clean, and limiting movement to slow down the spread of the venom. It is also important to calm the patient and ensure they receive a tetanus shot. Bandages can be applied gently to allow blood flow but limit the flow of lymphatic fluid to reduce the amount of venom entering the body. Tourniquets, sucking out the venom, and applying ice are not advised. Medications that could weaken muscles or impair lung function should be avoided. All suspected coral snake bites need to be closely monitored for at least 24 hours, as the venom can cause life-threatening breathing problems. If breathing difficulties occur, the patient may need to be intubated and treated with an antidote or other drugs. The North American Coral Snake Antivenin (NACSA) is a standard antidote made from horse antibodies and is typically used at the first sign of breathing problems or neurological symptoms. However, its use for preventing symptoms in patients without visible signs of venom effects is up for debate. It is recommended to contact the Poison Control Center or a toxicologist for advice on treatment. Checking for signs of allergic reactions is vital when administering NACSA, and if an allergic reaction occurs, the antidote should be stopped immediately and other medications may be administered based on the patient's symptoms. If coral snake antivenom is not available, doctors might try a dose of anticholinesterase medication such as neostigmine, but this should be done with guidance from a poison control center or toxicologist.

When treating Coral Snake Toxicity, there are potential side effects to be aware of. These include: - Allergic reactions: Hives, difficulty breathing, low blood pressure, and swelling can occur as immediate or delayed hypersensitivity reactions to the antivenom. If an allergic reaction occurs, the antidote should be stopped immediately and other medications such as epinephrine, antihistamines, corticosteroids, and albuterol may be administered based on the patient's symptoms. - Excessive cholinergic effects: If there is no coral snake antivenom available, doctors might try a dose of anticholinesterase medication such as neostigmine to counteract the effects of the venom on the nervous system. However, this should be given with an anticholinergic medication like atropine or glycopyrrolate to prevent potential excessive cholinergic effects. Consulting with a poison control center or toxicologist is recommended for guidance. - Limited supply of antivenom: The North American Coral Snake Antivenin (NACSA), which is the standard antidote, has a limited supply due to production stopping in 2006 and any existing vials expiring. Obtaining the required antivenom could take time and resources as it might not be readily available.

The prognosis for Coral Snake Toxicity can vary depending on the severity of the bite and the promptness of medical treatment. However, it is important to note that being bitten by a coral snake is rare compared to bites from pit vipers. While their venom is very potent and can cause serious nerve damage and difficulty with breathing, there has been just one recorded death in North America due to a bite from a coral snake.

Toxicologist or Poison Control Center.

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