Are Tarantulas Poisonous or Venomous?

inverttparty
Aug 11
2 min read

Tarantulas often get a bad reputation thanks to myths, movies, and general spider fear. One of the most common misconceptions is that tarantulas are “poisonous.” In reality, tarantulas are not poisonous — they are venomous. Many people get the two mixed up, so this guide is here to help.

Before continuing though, it's worth mentioning that tarantulas are not inherently aggressive. They are defensive and will only bite if absolutely provoked. I have never been bitten in all my years of working with tarantulas.

Venomous vs Poisonous — What’s the Difference?

Venomous animals deliver toxins through a bite, sting, or other specialised mechanism.
Poisonous animals are harmful to eat or touch because their toxins are absorbed through the skin or ingested.
Essentially, if you bite it, and you get harmed, it is poisonous. But if it bites you and you get harmed, it's venomous.

Example:

Venomous — snakes, scorpions, tarantulas.
Poisonous — poison dart frogs, some pufferfish, certain plants.

So, a tarantula can bite and inject venom, but eating one (not that this is recommended!) or touching it won’t poison you.

Tarantula Venom — What Does It Do?

Tarantula venom is primarily used for subduing prey, not attacking humans. It contains enzymes that help break down the insect’s insides so the tarantula can consume it.

For humans:

A bite from most new world tarantulas (tarantulas from the western hemisphere) is comparable to a bee sting — mild pain, redness, and swelling. A bite from old worlds (tarantulas from the eastern hemisphere) can however cause longer term symptoms, with some being deemed medically significant.
Serious reactions are rare and usually linked to allergies, just like with insect stings.

What About Urticating Hairs?

While tarantulas aren’t poisonous, some species (especially New World tarantulas) have urticating hairs on their abdomen. If flicked into skin or eyes, these tiny barbed hairs can cause irritation — but this is a mechanical defence, not poison or venom.

Why the Misconception?

The terms “poisonous” and “venomous” are often mixed up in casual conversation and pop culture. Movies and TV shows also tend to exaggerate the danger of spiders for dramatic effect, fuelling the confusion.

Key Takeaways

Tarantulas are venomous, not poisonous.
Their venom is mainly for hunting and defence, not harming humans.
Bites are rare and generally mild, but respect their space to avoid stressing the animal.
Handling is best kept to a minimum — admire from a safe distance.