If a child or a baby is bit by something that we suspect to be poisonous, it's important that we try and identify what that species is. For example, an insect, a spider. We would like you to bring that to the hospital with the baby or child, so we can ensure proper treatment. In many cases, there will not be evidence of what the baby, so we have to go with our best guess. Or immediate concern is an allergic reaction. Allergic reactions to certain kinds of poisons can be life threatening. Usually, the first bite, however, or the first exposure is not a life threatening one and may just cause a lot of swelling. The best course of action is to get to a hospital so that you can get the proper treatment.