My brother was bitten by one once. He woke up with one on his arm. He already had a little crater on his elbow where the spider was. He was in pain so he went to our Mother's as she was an EMT. By then he had a red line running up his arm, so she took him to the ER. The doctor said the red line was headed for his heart, and if he had waited much longer, it would have killed him. It really made a mess out of his arm. I've had them run out of things I've had in storage, but I think they just wanted to get away.