Signs & Symptoms of a Funnel Web Spider Bite

There are more than 40 species of funnel-web spiders, according to the Australian Museum, and they live almost exclusively in eastern Australia. Though not all species are poisonous, the ones that are are among the most dangerous spiders on Earth. Before the introduction of anti-venom in 1981, funnel-web spider bites were sometimes fatal. These bites produce symptoms that start locally but can spread rapidly if not treated and cause serious health problems.

Pain

• Funnel-web spider bites cause extreme localized pain, according to the National Institutes of Health (NIH). If the bite is not treated immediately with anti-venom, the reaction can progress to include pain in the joints. Head pain, as with a headache, may also be a symptom.

Muscle Spasms

• According to the NIH, muscle spasms most often occur in the abdomen and legs and can be extremely painful. The bites can also cause muscle twitching, which can be either minor or uncontrollable, and numbness, most often around the mouth and lips, which can lead to drooling.

Lung and Heart Problems

• According to eMedicine.com, rapid heart rate and increased blood pressure are common symptoms. Difficulty breathing and pulmonary edema (fluid in the lungs) may also occur.

Agitation and Confusion

• Funnel-web spider venom contains a neurotoxin. Signs of a serious envenomation (or poisoning) include agitation and confusion, according to eMedicine.com. The bites can also produce double vision. In rare cases, loss of consciousness and even coma can occur.

Feelings of Illness

• Nausea and vomiting are common after a funnel-web spider bite, according to eMedicine.com. Other symptoms of illness, according to the NIH, include diarrhea and chills.