Medications

The person bitten by a black widow spider, who has pain severe enough to seek treatment at an Emergency Department, will require narcotic pain relief. Muscle relaxants given by injection may also be of value. Although calcium gluconate given through an IV has long been advocated, it does not seem to produce much relief of symptoms.

Use of antivenin

The antivenin available for treatment of black widow spider bites is derived from horse serum. The venom produced by various species of black widow spiders is similar, so the antivenin (antivenin) prepared against one venom is effective against the others. Antivenin is produced by gradually increasing injections of the specific venom in a horse. The horse then starts producing the antivenin, which will be used in humans.

Symptoms are often not easily relieved, even with narcotics. Some experts recommend that antivenin be used in any severe bite because one vial of the antitoxin produces significant and rapid relief of symptoms. It can even be used if there is delay in reaching the hospital. Yet other sources recommend that antivenin be used only in children, the elderly, and those with severe underlying medical conditions.

Horse serum-based antivenin carries a significant risk of a severe allergic reaction (anaphylaxis) which can be life-threatening. Skin testing before the serum is administered is therefore recommended. Although another side effect known as serum sickness (characterized by skin lesions, fever, pain in the joints, and swollen lymph glands) is common when horse serum is used to treat rattlesnake bites, it is uncommon when used to treat black widow spider bites (probably because of the low dose needed for relief).

Be aware, however, that this antivenin may not be readily available at most hospitals; there may be some delay or difficulty in obtaining it when needed.

Note: The use of the black widow antivenin might sensitize the person against later use of rattlesnake antivenin. Obviously, the physician should discuss lifestyle habits that might affect the person's risk of incurring a snakebite in the future. In many areas, black widow bites are much more common than rattlesnake bites.