Experts in the field often say that spider identification is tricky since very many species resemble each other, and the venomous and the non-venomous ones are found in a complex who's who relationship. Presently, there are all sorts of devices that allow people to catch and analyze the spiders that live in their homes so as to find out whether they are poisonous or not. Without being lethal for a human being, poisonous spiders can cause very advanced tissue damage known as necrosis. There is a whole range of symptoms, one nastier than the other that accompany the bite of a dangerous spider: digestive troubles such as nausea and vomiting, headaches and fever, not to mention the local discomfort manifested as pain and itchiness. The black widow spider is not capable of killing a bird that would eat it, but the digestive sickness that would follow, will be definitely enough to make it avoid attacking the black widow again. The female black widow spider is more venomous than the male, and it is she the biggest threat to predators. There is one thing that definitely sets the brown recluse spider apart from other fellow-spiders: the way it hunts. The whole purpose of weaving a web or creating a maze of threads is to make the perfect trap for catching prey; yet, the brown recluse spider does not consider that enough. The males are likely to leave their nest and go hunt somewhere else, while the females will not go far from the web. A cold cloth pressed on the wound will reduced the swelling and the redness associated with spider bites in general. The immediate drug treatment of risky spider bites usually includes the administration of an anti-venom based on corticosteroids. The administration of specific medication can only be done by authorized medical personal and when the circumstances indicate a toxic venom exposure. The greatest risk of a spider bite is anaphylaxis: the allergic reaction to spider venom that is sometimes encountered with very sensitive people. Hives, wheezing, shortness of breath and weakness are the general symptoms associated with anaphylaxis, therefore call 911 right away if you notice any such symptoms.