Spider Bite
Symptoms, Causes, Treatments, Questions & Related Topics

Possible Symptoms of a Spider Bite

1. Pain or Itching

When a spider bites you, just like a bug bite, even if it is not an extremely poisonous bite that requires hospitalization, the area around the bite usually hurts. The pain could feel as if it radiates from the bite, and it might itch.[1]

2. Swelling

The area around the bite is likely to swell or become larger, turn red or purplish in color, and potentially even show the signs of a rash that consists of flaky, irritated skin. Keep an eye on the spot where the spider bit you in order to make sure that it doesn’t get larger very quickly.

3. Anxiety

Most people become very nervous after they have been bitten by a spider, partially because it’s difficult and sometimes impossible to know whether the spider was poisonous.[1] Try to stay calm. If someone you know was bitten, help them stay calm as you determine what to do next.

4. Illness

Spider bites sometimes cause symptoms of the flu or another illness: sweating, fever, chills, nausea, vomiting, headache, and swollen glands.[2] These symptoms do not necessarily indicate a bite from an extremely poisonous spider. It is important to keep an eye on the bitten individual and their current state of wellness. If the symptoms start to get worse, if they do not go away over time, or if the individual finds it hard to breathe, they need medical treatment.

5. Anaphylactic Shock

Some people are allergic to spider bites.[3] If this is the case, the individual could go into anaphylactic shock; symptoms include wheezing, coughing, a swollen tongue, trouble breathing or talking, dizziness, and loss of consciousness. Anaphylactic shock is a medical emergency that requires immediate treatment.

Top 3 Causes of Spider Bites

1. Harmless Spiders

Most spiders are not poisonous to humans (except for those who have allergic reactions to spider bites), and their bites are not deadly. Sometimes, painful and uncomfortable symptoms can still occur as a result of a bite, but usually, they are not dangerous. In many cases, a spider bite is no more serious than a bee sting.[4]

2. Black Widow

Two types of venomous spiders are common in North America. One is the black widow, usually found in the Southern and Western United States.[5] Black widows are black all over with a red mark on their bodies. People who are bitten by black widow spiders have usually accidentally come into contact with a spider’s web in an outdoor area that isn’t cleaned often where there is debris or old wood. The black widow makes two marks deep in the skin and pumps its venom into the body. A black widow bite requires immediate medical help.

3. Brown Recluse

The brown recluse spider is the other type of dangerous spider native to the United States. It can usually be found in the Midwest and in the South.[5] Brown recluse spiders can be hard to tell apart from less dangerous spiders. They are brown, they have a marking shaped like a violin on their heads, and they have six eyes instead of eight. They can usually be found in dry areas that are sheltered from the heat or indoors in cool, dark places such as closets. A brown recluse bite usually turns white, looks like a blister, and causes a tingling sensation. This dangerous bite can cause the skin to develop necrosis.

3 Ways to Prevent a Spider Bite

1. Don’t Upset a Spider

Most spiders do not bite a human unless they feel threatened.[4] If you see a spider out in the wild, it’s best to simply leave it alone.

2. Protect Yourself

Wear long-sleeved shirts and gloves when you work outside to avoid being bitten by spiders.[6] If you know you’re allergic to spiders, make sure you have an EpiPen or another kind of medication handy in case of a bite. Spray your clothes with insect repellent, especially those in your closet, to avoid brown recluse spiders making a home there.

Possible Spider Bite Treatment Options

1. Wash and Self-Treat

If you have been bitten by a nonpoisonous spider, you should be able to wash the bite with soap and water, use an ice pack to minimize swelling, and take over-the-counter painkillers to treat any pain or discomfort.[4] Most of the time, the swelling and other symptoms go away on their own.

2. Get Help

If you have trouble breathing or show any signs of shock, get help by calling 911 or going to the hospital immediately. These are signs that your body is reacting to a poisonous bite. If the symptoms do not subside in a few days, or if they worsen, you might require further medical treatment. If you think you saw a poisonous spider bite you, it is better to seek medical help than to wait and see what happens.

Questions Your Doctor May Ask About Your Spider Bite

  • How long ago did the spider bite you?
  • Did you see what the spider looked like?
  • What does the bite look like?
  • Have your symptoms subsided, worsened, or stayed the same over time?

A Spider Bite May Also Be Known as

  • Arachnid bite
  • Arachnidism


  1. Centers for Disease Control and Prevention. Venomous Spiders. https://www.cdc.gov/niosh/topics/spiders/symptoms.html
  2. Healthline. Spider Bites. https://www.healthline.com/health/spider-bites
  3. HealthDirect. Spider Bites. https://www.healthdirect.gov.au/spider-bites
  4. National Library of Medicine. Spider Bites. https://medlineplus.gov/spiderbites.html
  5. Centers for Disease Control and Prevention. Types of Venomous Spiders. https://www.cdc.gov/niosh/topics/spiders/types.html
  6. Occupational Safety and Health Administration. Brown Recluse Spider. https://www.osha.gov/OshDoc/data_Hurricane_Facts/brown_recluse_spider.pdf

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