What to Know About Dangerous Animal Bites

In some geographic regions and climates, a variety of poisonous creatures can thrive and pose a real threat to humans in the vicinity. Bites from some types of snakes, spiders, scorpions, and even wasps and certain snails, can induce rapid physiological changes in the body resulting in neurological impairment and even stroke.

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Venom emitted from an animal bite or an animal sting may possess chemical properties that can cause paralysis of the muscles which can impair breathing and heart function with potentially fatal consequences. Some types of venom may disrupt normal blood clotting function, provoke excessive bleeding, stimulate hormone release and alter blood vessels. These consequences can occur suddenly sudden and may be severe due to the surge of venom released into the body of the victim.

Snake Bites

There are numerous reports of snake bites resulting in serious medical emergencies such as stroke. A viper snake, which can be found in many locations all over the world, has been identified as a source of stroke in humans. The venom released into the bite victim’s circulation contains a number of toxins that produce a complex interaction with the human body.

Toxin effects include excessive bleeding, which triggers hemorrhage in multiple organs of the wounded individual. And interestingly, sometimes the toxins in the venom cause the opposite effect, resulting in blood clots in the brain or other structures of the body.

Other poisonous snakes, such as rattlesnakes, discharge venom into the system of the injured victim, which causes a combination of bleeding and blood clots throughout the body. Proteins such as metalloproteinases, serine proteases, and C-type lectin, found in snake venom, have anticoagulation and pro-coagulation activity.

Effective treatment includes antivenom as well as urgent medical assessment and care, including respiratory, cardiac and kidney support. Setbacks in effective treatment have been reported when there is a delay in reptile identification and anti-venom administration.

Spider Bites

Spider bites are associated with muscle paralysis due to the direct action of neurotoxins on nerve and muscle transmission. Muscle paralysis can target any of the muscles throughout the body, including the muscles that support vital functions such as breathing and heart contraction. Spider venom also can cause severe coagulation disorders, resulting in a stroke.

Similar to the medical management of venomous snake bites, emergency management of toxic spider bites includes rapid and vigilant injection of anti-venom treatment.


The sting of some varieties of scorpions can cause a number of life-threatening consequences, including heart rhythm irregularities, muscle paralysis, and respiratory impairment. Additionally, the scorpion venom may directly interfere with the normal process that regulates bleeding and blood clotting. Scorpion stings induce the excessive activity of catecholamines, which are excitatory hormones. Overactivity of catecholamines can induce extreme changes in blood vessel diameter, spasm of cerebral blood vessels, and abnormal heart rhythm reactions.


The vast majority of snails are harmless. There are some species of marine snails that feed on fish and can cause injury to humans due to their venom which may induce paralysis.

A Word From Verywell

An animal bite can be perilous for the victim. Urgent medical attention is always necessary, as life-threatening symptoms may evolve rapidly. The indigenous animal species varies depending on the environmental locale and the climate, and emergency medical workers may be familiar with the dangers of native species and their effective treatments.

Systemic medical care is often necessary to counteract the physiological effects of noxious components of the venom. Often, administration of anti-venom is necessary to stop the sustained action of the poisonous material injected through a bite or a sting.

While you may not consider taking a 'selfie' a suitable response to a snake or scorpion bite, experts advise taking a photo of the animal, as identification of the species that bit you is key to getting you the right anti-venom and preventing future medical complications.

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  1. Association of ischemic and hemorrhagic cerebral stroke due to severe envenomation by the Sahara horned viper (Cerastes cerastes), Aissaoui Y, Hammi S, Chkoura K, Ennafaa I, Boughalem M, Bulletin de la Société de pathologie exotique, August 2013

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