Are Brown House Spiders Poisonous? Facts and Information

A common sight in most North American homes, the brown house spider is generally considered harmless.

They won’t attack and bite unless threatened, and their venom is not harmful to humans and typically only causes localized pain and swelling.

Although its bite is not poisonous, it can be pretty painful, and cause minor irritation and discomfort. Additionally, severe allergic reactions to their bites have been reported in some cases where the person had an underlying condition.

Common Characteristics of Brown House Spiders

Brown house spiders are small, 8-legged creatures that are often found in dark, secluded places. Their brown coloration helps them to blend in with their surroundings, making them difficult to spot.

These spiders typically measure between 1/4 and 3/8 inches in length, and their bodies are covered with fine hairs.

top view of brown house spider on white surface

These spiders are also known for their webs, which they spin in dark corners and crevices. The webs are often messy and unkempt, with tangled strands of webbing stretched between furniture and other objects.

While brown house spiders do have fangs, they are not considered to be dangerous to humans. Their venom is not strong enough to cause serious harm, and these spiders rarely bite unless they feel threatened. However, some people may experience minor swelling and redness at the site of a brown house spider bite.

Brown house spiders typically mate during the autumn months. After mating, the female lays her eggs inside a silken sac.

The eggs hatch after about two weeks, and the young spiders begin to spin their own webs. Brown house spiders generally live for one to two years.

Brown House Spider Behavior and Diet

Native to Australia and found in other countries, brown house spiders are most commonly found in the United States. These spiders often enter homes through open doors and windows and can also be transported inside boxes and furniture. Once they are inside, they will spin their webs in dark corners and crevices.

Brown house spiders generally eat insects that get caught in their webs. They will also sometimes eat other spiders. These spiders are nocturnal and will typically only come out to hunt for food at night.

If you have a brown house spider in your home, there is no need to be alarmed.

These spiders generally pose no threat to humans and are considered to be relatively harmless. However, if you experience any adverse reactions to their bites, it is important to seek medical attention.

What to Do If You Got Bitten by a Brown House Spider

It’s the middle of the night. You’re asleep in your bed, soundly dreaming of sugarplums and fairies. Suddenly, you feel a sharp pain in your arm.

You bolt upright, heart-pounding, and see a small brown spider scurrying away. You’ve been bitten by a brown house spider. Now what?

close up of human skin with spider bite

First, don’t panic. The bite of a brown house spider is not poisonous and will not cause any long-term damage. However, it is essential to clean the wound thoroughly to prevent infection. Apply an antibacterial ointment and cover with a bandage. This is to prevent the injury from getting infected.

If the pain persists or you experience any unusual symptoms, such as swelling or difficulty breathing, seek medical attention immediately.

Brown House Spiders vs. Brown Recluse Spiders

Brown house spiders and brown recluse spiders are often confused for one another. Both are brown, small, and can be found in homes. However, there are some critical differences between these two types of spiders. Here are some of the key differences:

close up of brown recluse spider on wooden surface

Brown House Spiders are Not Poisonous

One of the key differences between brown house spiders and brown recluse spiders is that brown house spiders are not poisonous. Their venom is not harmful to humans, and they will not bite unless they feel threatened.

On the other hand, brown recluse spiders are poisonous. Their venom is harmful to humans and can cause serious health problems such as necrosis (tissue death) and organ damage.

If you are bitten by a brown recluse spider, it is important to seek medical attention immediately.

Brown House Spiders are Not Aggressive

Another key difference between brown house spiders and brown recluse spiders is that brown house spiders are not aggressive.

They will only bite if they feel trapped, threatened, or needed to look for a way to escape. In contrast, brown recluse spiders are aggressive and will often bite without provocation.

If you see a brown recluse spider, it is important to exercise caution and avoid contact if possible.

Size Differences

While these two species share a number of physical characteristics, there are some key differences between them.

For example, brown recluse spiders are generally larger than the average brown house spider. They can be anywhere from half an inch to an inch long, while brown house spiders rarely grow larger than a quarter of an inch in length.

Additionally, whereas the legs of a brown house spider bristle with fine hairs, those of a brown recluse are completely smooth and hairless.

Color Differences

There are also some differences in color between these two types of spiders. Brown recluse spiders tend to be a light brown or tan color, while brown house spiders are typically darker brown.

Additionally, while brown recluse spiders have a dark “fiddle” shape on their backs, brown house spiders do not have this marking.

Habitat Differences

Finally, brown house spiders and brown recluse spiders differ in their preferred habitats. The Brown House Spider is commonly found in, you guessed it, houses!

They build their webs in dark corners and generally stay close to the ground. In contrast, Brown Recluse Spiders are often found outdoors in wooded areas or on undisturbed leaves and debris piles.

They are also more likely to build their webs high up off the ground. Though both spiders are reclusive by nature and prefer to stay hidden away, their different habitats mean that homeowners are much more likely to come into contact with a Brown House Spider than a Brown Recluse Spider.

Final Thoughts

Brown house spiders are not poisonous despite their scary physical characteristics and appearance. They’d only sink their fangs into you if they feel threatened, so there’s no need to worry about them unless you’re handling them directly.

In general, it’s always best to avoid contact with any spider, but if you do come across a brown house spider in your home, there’s no need to be alarmed. Just gently remove it and release it outside.

And remember, if you ever have any doubts about whether a spider is poisonous or not, it’s always better to err on the side of caution and seek medical attention as soon as possible.