How about... try to stop doing it?
Even if you do visit a doc & they give you a bunch of meds. IT IS NOT GOING TO HELP if you will continue with binging & purging. You are engaging in a destructive behavior & it's not just going to go by without a mark/harm on your body.
"Self-induced vomiting:
Damages the digestive system: it can cause a peptic ulcer which is an area of the stomach or duodenal lining which becomes eroded by stomach acid. These are known as peptic ulcers. The symptoms can vary, with some people not noticing anything out of the ordinary but others may vomit blood and experience abdomen or chest pains. The pain is usually increased when the individual eats or drinks. Peptic ulcers can be serious and need immediate attention if you are vomiting blood or passing digested blood in your stools."
http://www.eatingproblems.org/epseffect.html