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Not all bites or stings are the same. You will need different first aid treatment and medical care depending on what type of creature has bitten or stung you. Some species can cause more damage than others. Some people also have allergies that raise the risk of a serious reaction.
Here’s how to recognize and treat the symptoms of bites and stings from insects, spiders, and snakes.
Nearly everyone has been bitten or stung by an insect at one time or another. Whether you’ve been attacked by a mosquito, fly, bee, wasp, ant, or other bug, insect bites and stings usually cause a mild reaction. Your body reacts to venom or other proteins that insects inject into you or transfer to your body through their saliva. This can result in symptoms at the site of the bite or sting, such as:
The severity of your symptoms can vary, depending on the type of insect that bites or stings you. Some people also develop a severe allergic reaction to insect stings or bites. Bee and wasp allergies are particularly common. A severe allergic reaction can cause:
If you or someone you know begins to experience these symptoms shortly after being bitten or stung by an insect, call 911 or local emergency services. A severe allergic reaction that affects multiple parts of your body is called anaphylaxis. It can be life-threatening if not treated promptly.
If you’ve ever had a severe reaction to an insect bite or sting, ask your doctor about allergy testing. If you’ve been diagnosed with a severe allergy, your doctor should prescribe a medication called epinephrine. You can use a preloaded epinephrine auto-injector (e.g., EpiPen®) to inject the medication in your outer thigh muscle. It acts quickly to raise your blood pressure, stimulate your heart, and reduce swelling of your airways. You should carry it with you at all times, especially when you’re outdoors in areas where you might encounter insects.
If someone shows signs of a severe allergic reaction, help them get emergency medical attention and follow the steps in the next section. If they show no signs of a severe reaction, treat the site of the bite or sting for minor symptoms:
If you suspect someone may be having a severe allergic reaction:
To avoid making matters worse, don’t apply a tourniquet. You should also avoid giving them anything to eat or drink.
Most spider bites are relatively harmless. Anywhere from several hours to a day after you get bitten, you may notice symptoms similar to those of an insect sting or bite. At the site of the bite, you may experience:
Some types of spiders can cause more serious reactions, including black widow and brown recluse spiders. If you know what to look for, it’s easy to identify both of these species.
Fully grown black widow spiders are about 1/2-inch long. They have a black body with a red hourglass marking on the underside of their abdomen. Some black widow spiders also have red spots on the upper surface of their abdomen and crosswise red bars on the underside.
Black widow spider venom causes problems with your nervous system. Within a few hours of being bitten, you may notice intense pain at the site of the bite. You may also experience other symptoms, such as chills, fever, abdominal pain, nausea, and vomiting.
Fully grown brown recluse spiders are larger than black widow spiders. They’re about 1 inch in length. They vary in color from yellowish tan to dark brown. They have a violin-shaped marking on the surface of their upper body, with the base of the violin facing toward their head and the neck of the violin pointing toward their rear.
Brown recluse spider bites cause damage to your skin. Within about eight hours of being bitten, you will experience redness and intense pain at the site of the bite. Over time, a blister will develop. When the blister breaks down, it will leave a deep ulcer in your skin, which can become infected. You also may develop symptoms such as fever, rash, and nausea.
If you suspect that someone has been bitten by a brown recluse or black widow spider, help them get medical treatment immediately and follow the steps in the section. Otherwise, treat their spider bite like you would most insect bites and stings:
If you suspect that someone has been bitten by a brown recluse or black widow spider:
Don’t apply a tourniquet. Avoid giving them anything to eat or drink.
While many snakes are harmless, the bite of some species can be poisonous and even deadly. Common species of poisonous snakes in the United States include:
Symptoms of a poisonous snake bite can vary, depending on the type of snake. They can include:
A poisonous snake bite is a medical emergency. Prompt treatment can minimize symptoms and promote recovery.
If someone has been bitten by a snake, and you suspect it may be poisonous, help them get emergency medical treatment and follow the steps in the next session. If you know the snake wasn’t poisonous, treat the area of the bite for bleeding and other symptoms:
If the person is experiencing severe bleeding, help them get emergency medical treatment. Continue to apply new layers of cloth or gauze to the bleeding area, on top of layers that have been soaked through with blood. Removing old layers can make the bleeding worse.
If you suspect that someone has been bitten by a poisonous snake:
To avoid making things worse, do not:
Most people are bitten or stung by insects, spiders, or snakes at some point in their lives. For mild bites and stings, basic first aid treatment is usually enough. Treat the area for minor bleeding, swelling, pain, and itching.
If you suspect that someone may be having a severe reaction to a bite or sting, help them get medical attention right away. People with certain allergies may have a severe allergic reaction to a bite or sting. Some critters, such as black widow spiders, brown recluse spiders, and poisonous snakes can cause a lot of damage. Being prepared for possible emergencies can help you keep yourself and others safe.
Written by: Linda Hepler, RN
Medically reviewed on: Jul 25, 2016: Deborah Weatherspoon, PhD, RN, CRNA, COI
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