This blister breaks open leaving an open ulcer that scabs over. The ulcer can enlarge and involve underlying skin and muscle tissue. Pain may be severe. A generalized red, itchy rash usually appears in the first 24-48 hours. Other symptoms include fever, chills, nausea, vomiting, muscle aches and hemolytic anemia.
Treatment consists of washing the wound.
In case of infection, an ulcer that does not heal or a rash, see a physician. The black widow is a shiny, inky black spider with a large round tail segment. Only the female is dangerous to humans. Including its legs, the black widow generally measures from one-half inch to one inch in length. Red to orange colored markings, usually in the shape of an hourglass, are always found on the underside of the belly.