×

Please Remove Adblock
Adverts are the main source of Revenue for DoveMed. Please remove adblock to help us create the best medical content found on the Internet.

First Aid for Black Widow Spider Bite

Last updated March 3, 2018

Black Widow Spider Bite may occur following contact with a black widow, generally when they are inadvertently disturbed.


What is Black Widow Spider Bite?

  • The black widow spider is a medium-sized venomous spider with a red hourglass marking on its belly. The spider is found in many parts of the world
  • Black Widow Spider Bite may occur following contact with a black widow, generally when they are inadvertently disturbed
  • The spider bite is painful and may cause nausea, vomiting, and severe muscle cramps. However, the condition is rarely fatal in normally healthy humans

What are the Causes of Black Widow Spider Bite?

  • Humans are generally bitten by the female black widow spider (which may be 1.5 inches in size), mainly when they are disturbed or while protecting their eggs
  • The spiders are active at night and may be found in dark corners and nooks. However, they are usually not found in places where humans live or reside

What are the Signs and Symptoms of Black Widow Spider Bite?

The signs and symptoms of Black Widow Spider Bite can vary from one individual to another and may be mild or severe. In general, the signs and symptoms may include:

  • Sharp pain at the bite site
  • Severe muscle cramps from effects of the toxin/venom
  • Nausea and vomiting
  • Drooling and increased sweating
  • General weakness
  • Light-sensitivity
  • Neurological symptoms including anxiety, feeling restless, and dizziness
  • Abdomen, shoulder, back, or chest pain
  • Decrease in blood pressure (hypotension)
  • Tremors
  • Fainting
  • Convulsions are rarely observed (in children)

How is First Aid administered for Black Widow Spider Bite?

First Aid tips for Black Widow Spider Bites:

  • Call the Poison Control Center at 1-800-222-1222 (or your local poison control center) for further instructions
  • Clean the bite site with soap and water
  • Put a wet, cold cloth, or an ice pack on the bite site
  • Use topical antibiotic cream on the bite spot
  • Consider taking antihistamine for allergic reactions and aspirin or acetaminophen to relive pain
  • Seek medical advice, before giving any kind of medications to children
  • Do not apply a tourniquet, since the harm caused by the compression of the tourniquet may be significantly more than its benefits
  • Seek medical help, in case of severe symptoms or an allergic reaction
  • If safely possible, take the spider (or parts of it) to the healthcare facility for identification

At the healthcare facility: Anti-venom serum is seen to be effective, when there is severe pain that does not get better with the above measures, or when there is a risk of life-threatening complications, and to decrease the need for hospitalization.

Who should administer First Aid for Black Widow Spider Bite?

The individual who is affected, or someone near should administer initial first aid, following which one should seek medical help.

What is the Prognosis of Black Widow Spider Bite?

  • The prognosis is dependent on the location of bite, the severity of reaction, and the overall health of the individual
  • In most cases, the prognosis of Black Widow Spider Bite is typically good with appropriate home care or treatment
  • Usually the signs and symptoms last 3-7 days after the bite; occasionally, it may last up to a month

How can Black Widow Spider Bite be Prevented?

Black Widow Spider Bites may be prevented by:

  • Avoid being outdoors at night in forested areas
  • Use pest control in areas where the spiders are found in large numbers
  • Use insect repellent such as DEET
  • Wear clothes that cover the entire body while outdoors in the evenings or at nights
  • Avoid wearing clothes or shoes that have been lying around undisturbed for a while, without first inspecting them thoroughly
  • Do not reach into dark nooks/corners/recesses of the house with your bare hands/foot
  • Do not let clutter accumulate in various parts of the house (such as in the cellar, garage, closets, etc.)

What are certain Crucial Steps to be followed?

  • Call 911 (or your local emergency help number), if the condition is serious
  • Administer antihistamines, if the individual has an allergic reaction

What are some Useful Resources for Additional Information?


References and Information Sources used for the Article:


Helpful Peer-Reviewed Medical Articles:


Reviewed and Approved by a member of the DoveMed Editorial Board
First uploaded: Aug. 27, 2017
Last updated: March 3, 2018