Tarantulas are often perceived as intimidating creatures. Their size and hairy appearance spark curiosity and sometimes fear, leading many to question the danger of their bites. This article clarifies the nature of their defensive capabilities.
Understanding Tarantula Venom
Tarantulas are venomous, not poisonous. The distinction lies in the method of toxin delivery: poisonous substances cause harm when ingested or absorbed, while venomous ones are injected, typically through a bite or sting. Tarantulas possess fangs, which they use to inject venom into their prey. Their venom is primarily used to subdue insects and small animals, allowing the tarantula to liquefy and consume its meal.
Despite their ability to inject venom, tarantula venom is mild and not medically significant to humans. For most people, a tarantula bite feels similar to a bee sting. While some Old World species (Africa, Asia) may have more potent venom, New World species (Americas) often utilize a different defense mechanism involving specialized hairs. No human deaths have been directly attributed to tarantula venom.
Common Reactions to a Bite
When a tarantula bites, the immediate sensation is a sharp pain at the site. The area may become warm, red, and swollen, with some individuals also experiencing itching. This localized discomfort usually subsides within a few hours, though pain can occasionally persist longer.
While most reactions are confined to the bite area, systemic reactions are rare but can occur, especially in individuals with sensitivities. These may include nausea, muscle cramps, or a general feeling of malaise. In infrequent cases of allergic reaction, symptoms could escalate to difficulty breathing, widespread skin rashes, or swelling of the lips and throat. Despite these potential reactions, the bites are not life-threatening to humans.
Beyond the Bite: Urticating Hairs and Care
Beyond their bite, many New World tarantulas possess another primary defense: urticating hairs. These tiny, barbed hairs are located on their abdomen and can be actively flicked or rubbed off by the tarantula when it feels threatened. The hairs are designed to embed themselves in the skin or mucous membranes of predators, causing irritation.
Contact with urticating hairs causes itching, redness, rashes, and sometimes bumps or blisters on the skin. If the hairs get into the eyes, they can cause significant irritation, pain, and potentially lead to conditions like ophthalmia nodosa, requiring medical attention. Inhaling these hairs can also cause respiratory irritation, leading to symptoms like coughing or difficulty breathing. The irritation from these hairs can last for weeks.
First Aid and When to Seek Medical Attention
If bitten by a tarantula, wash the bite area thoroughly with soap and water to prevent infection. Apply a cold compress to reduce pain and swelling, and use over-the-counter pain relievers for comfort. For exposure to urticating hairs, rinse the affected skin with cold water and apply a cool compress for relief. Antihistamine creams or oral antihistamines can also help manage itching and swelling. Seek medical attention if severe allergic reactions occur, symptoms worsen, or if hairs make contact with the eyes.