My youngest of 3 boys did the same thing for 2 months last year. All of a sudden he wouldn't eat anything. We finally got him to eat his favorite salt and vinegar chips and some goldfish. He did drink milk a least 3 times a day though and that made us feel a little bit better. He started losing weight and I couldn't take it anymore and took him in to the doctor who had us do blood work. We did 2 different blood tests (5 vials later) and we even had to do an upper GI on him. We thought that maybe something was wrong with his esophagus. I went on to take him to a specialist after the upper GI came back normal, the specialist thought that maybe he had developed some kind of eating disorder. We went on the do some more testing. A week later he got sick with a really bad cold that made him vomit and after a day he must have gotten his appetite back because he started eating normally again. Hang in there, my oldest son gave me so much trouble that when I was pregnant with my second I went into pre-term labor because I was so stressed out with his lack of eating. I would act as if you don’t care (I know that sounds heartless but it might work) let him eat anything he wants; as long as he’s getting something in him he should be fine. He will go back to eating normally; it’s just a matter of time. Try not to stress too much, that reaction might be what he is looking for. Good luck!