Our 13-year-old son has what looks like a severe bug bite on his hand (maybe a spider bite?). Should I call the doctor? Is a visit to the emergency department necessary?
You can administer first aid by gently cleaning the area with mild soap and warm water. Some people feel better if they apply an antibiotic ointment or cream to the skin but this may not be necessary. If at all possible, collect the spider in a jar for identification. There are only two species in the United States that can cause bodily harm with their bites: the black widow spider (Lactrodectus) and the brown recluse or fiddleback spider (Loxosceles). "Fiddleback" refers to the violin shaped back of this spider. The brown recluse is considered by some experts to be the most dangerous spider to humans. But in their defense, they do eat cockroaches, silverfish and other soft-bodied insects. Not all states even have this type of spider. They are most common in the western, central, and southern states. The female black widow is commonly recognized by its black color, hour glass shape and red markings. Males are smaller, usually have yellow and red bands and spots over the back, and don't bite. Although they live in warmer climates (and desert areas), they can be found in states with cooler temperatures. The female black widow spider is probably the most venomous spider in North America. But it injects a very small amount of venom (poison) when it bites. Very few people actually die of spider bites. The bite of the brown recluse or black widow can cause local effects (pain, redness of the skin, an open wound) or systemic effects. In a very small number of people, deep wounds can develop from infection. The result can be necrosis (tissue death). The systemic symptoms are caused by the neurotoxic effects of the venom. Neurotoxins primarily target the nervous system. Systemic symptoms can include muscle cramping, sweating, nausea, vomiting, fever, chills, and dehydration. In less than one per cent of cases, the reaction can be severe enough to cause paralysis, respiratory arrest, and even death. Most of the time, local treatment of the skin is all that's required. A tetanus shot may be needed. Hospitalization is only necessary when there is a severe reaction with dehydration and/or compromise of the heart or lungs. Antibiotics are not used unless infection develops. Antivenin (an antidote to the poison) is not given routinely because symptoms go away quickly (within several hours to several days). Although there is a specific antivenin for brown recluse spider bites, it is not available in the United States. There aren't very many studies on the subject, but research evidence does not support the use of antivenin to prevent skin necrosis. Keep a close watch on your son for the next few hours to days. If he starts to develop any systemic signs, call your doctor immediately.