CPR First Aid

Is the Bite of a Black House Spider with a White Dot on Its Back Dangerous?

Is the Bite of a Black House Spider with a White Dot on Its Back Dangerous?

Is the black spider with a white dot on its back dangerous? Many people in Perth are wondering about this, as the spider has been spotted in many parts of the city. Furthermore, knowing if this spider is venomous may be helpful so a first aid response may be made if they bite. This includes applying first aid treatment to stop the flow of the venom before an antitoxin is available. Doing so may potentially save someone’s life. So, let’s find out if this black spider with a white dot on its back is dangerous and what first aid steps may be done if they bite you.

The Black Spider with a White Dot on its Back

This spider is identified as the Black House Spider (Badumna insignia) by the Australian Museum. It is one of the common spiders found in Perth.


The black house spider with a white dot on its back belongs to the Family Desidae along with other species Badumna longinquus. Sometimes, the black house spider is also called a window spider.

Physical Characteristics

Aside from the white dot on its back, this black house spider is also:

  • Dark and robust.
  • Dark brown to black in colour in terms of their carapace and legs.
  • In charcoal grey colour when it comes to their abdomen, with a dorsal pattern of white markings.

The female black spider with a white dot on its back is known to be larger than the male one.


The black house spider’s web form lacy silk sheets with funnel-like entrances, making it look like a funnel shape. This same shape is similar to the web of a funnel-web spider making people confused and mistakenly identifying the black spider as the venomous one. However, the silk of the black spider’s web is cleaner. As the web of a funnel-web spider has entrances that are disguised with detritus (eg, bark) particles embedded in the silk.


Black house spiders are found in the following spots:

  • Tree trunks
  • Logs
  • Rock walls
  • Buildings (in window frames, wall crevices, etc).

The black house spiders are also distributed in Perth.

Feeding and Diet 

Black house spiders feed on the following:

  • Flies
  • Beetles
  • Butterflies
  • Bees
  • Ants

They also eat household pests that are attracted to the light of windows and lamps. These are common spots where black spiders form their webs and live. This makes them more exposed to humans where they may potentially bite.

The Danger of a Black House Spider’s Bite

Even though the black house spider bites are venomous, they are not considered to be dangerous according to the Australian Environment Pest Managers Association. In addition, black house spiders are timid and there are not a lot of recorded bites from them. However, their bite may still impose painful symptoms.

Symptoms of a Black House Spider Bite

If a black house spider bite bites you, you may experience any of the following:

  • Nausea.
  • Vomiting.
  • Sweating.
  • Giddiness.

In some black house spider bite cases, skin lesions have developed after multiple bites.

First Aid to a Black House Spider Bite

To help alleviate the pain from a black house spider bite, you may do the following first-aid practices:

  1. Gently wash the area with soap and water.
  2. Apply an ice pack (it may be a cloth dampened with cold water or filled with ice) to the area of the bite for 10 to 20 minutes.
  3. Repeat step 2 until pain relieves.

If symptoms persist, it is advised to seek medical attention. Especially as a spider house bite may lead to an anaphylactic shock (anaphylaxis).

Understanding What Anaphylaxis Is

According to Britannica, Anaphylaxis is a severe, immediate, and possibly deadly systemic allergic reaction. This is caused by exposure to a foreign substance that a person has become sensitized to. One of these may be a spider house bite.

Signs and Symptoms of Anaphylaxis

The signs and symptoms of anaphylaxis include:

  • Hives
  • Itching
  • Flushed or pale skin
  • Low blood pressure
  • Swollen tongue or throat that may lead to wheezing or difficulty in breathing
  • Weak and rapid pulse
  • Nausea
  • Vomiting
  • Diarrhoea
  • Dizziness
  • Fainting

The above may occur minutes to hours after a black house spider bite.

First Aid Treatment for Anaphylaxis

The first aid response for anaphylaxis is the injection of epinephrine. It is done with appropriate dosage, administration, and injector such as an EpiPen auto-injector.

Who May Inject an Epinephrine?

Using an EpiPen auto-injector must be done with appropriate knowledge. It is part of the anaphylaxis first aid that a first aider or any medical professional may do.

What is a First Aider?

A first aider is someone who has enrolled in a first aid course in 123C Colin St West Perth 6005. As such, he/she may acquire the skills and knowledge in providing first aid response to emergencies. Some of these are black house spider bites and anaphylaxis. In addition, a first-aid certificate may also be acquired if the assessment is passed which may be required in some workplaces.

Workplaces that Require A First Aider

Aside from being able to respond to a black house spider bite, acquiring the first-aid certificate also allows you to be qualified in the following workplaces:

  • Retail shops
  • Offices
  • Libraries
  • Art gallery
  • Factories
  • Motor vehicle workshops
  • Forestry operations
  • Convenient store
  • Service stations
  • Freight transport
  • Schools
  • Education and care settings
  • Essential workplaces
  • Offices of a Fire Warden

The requirement for the number of certified first aider required in each workplace is published by Safework.

Why Certified First Aiders are Required in Workplaces?

A first aider is required in workplaces so first aid may be provided in case someone suffers an injury or illness while working. Aside from the access and/or availability of a first aider in the area, first aid kits are also required. These contain different items and among them are useful for responding to emergencies like a black house spider bite.

Workplace First Aid Kit

The Australian Standard AS2675-1983 lists the following items that must be in a workplace first aid kit:

  • Plastic Plaster 72x19mm
  • Fabric Premium Strip 72mm x 19mm
  • Burn Gel Sachet 3.5g
  • Antiseptic Spray 50ml
  • CPR Face Shield
  • Nitrile Examination Gloves
  • Gauze Swabs 7.5cm x 7.5cm 3’s
  • Eye Wash Ampoule 15ml
  • Cleansing Wipe
  • Splinter Probes 3.7cm
  • Low Adherent Dressing 5cm x 5cm
  • Low Adherent Dressing 7.5cm x 10cm
  • Low Adherent Dressing 10cm x 10cm
  • Conforming Bandage 5cm x 4M
  • Conforming Bandage 7.5cm x 4M
  • Heavyweight Conforming Bandage 10cm x 4m
  • Microporous Tape 2.5cm x 5M
  • BPC Wound Dressing #14
  • BPC Wound Dressing #15
  • Combine Dressing 10cm x 20cm
  • Triangular Bandage 110 x 110 x 155cm
  • Emergency Rescue Blanket
  • Eye Pads
  • Instant Ice Pack 80g
  • Scissor 13cm
  • Tweezer 11cm
  • Amputated Parts Bags Assorted Sizes
  • Notebook & Pen
  • Safety Pin
  • First Aid Leaflet

The above standard for a workplace first aid kit was released by Standards Australia, the country’s non-government, not-for-profit standards organisation.


The bite of a black house spider with a white dot on its back is venomous, but not considered to be very dangerous. Their bites may cause minor symptoms that may be treated with first aid. If it leads to anaphylaxis, an appropriate first aid response may be done too by injecting epinephrine. The first aid steps in treating a house spider bite and anaphylaxis are some of the contents in first aid courses in Perth.

Subscribe now & receive Exclusive DISCOUNTS on your booking!



More Posts