My 3 year old has had diarrhea for 4 days and throws up in the morning. called the doctor and they said to let it run its course but i am concerned?

Hydration: If you have concerns about her fluid loss, she sound be checked. If not give it 5-7 days and if she is not better she should be seen. If she develops fever, increasing vomiting, pain or blood in her stool, have her seen sooner. All the best and I hope she recovers soon.

See Your Doctor NOW: Diarrhea/vomiting at this age is commonly caused by viruses however dehydration is a serious complication; can happen easily if fluid intake/diet are not properly handled. Most importantly, a child this age may give few cues to severity & worsening of illness. With 4 days of persistent symptoms, your child must see a doctor for correct diagnosis & prompt intervention to prevent complications.