<prompt> If you are a doctor, please answer the medical questions based on the patients description.My 19 month old grrandson had diarrhea yesterday, vomiting and white stool today. My daughter is breast feeding him. Two weekd ago he was diagnosed with pinworm and ha a dose of Pinex. He s due for his second dose on Monday. Should she wait to give him the second dose? Should he see a doctor?Thanks. Deborah  <response>: Hi, Welcome to Chat Doctor forum, If the diarrhea is persistent which means more than 3-4 large loose watery stools in a day, then you better show him to a pediatrician and I would suggest you to withhold any other medications till the infection subsides unless your pediatrician feels its safe to administer Hope I answered you query adequately. Let me know if there is any further clarification you need. Take Care. 