One and a half year old baby vomiting and diarrhea is most likely the manifestation of gastroenteritis, this time to do some adjustments from the diet and medication. Specifically as follows: 1, diet, if some babies after drinking milk, there will be vomiting, diarrhea increased, you can drink less milk, more porridge or noodles, to ensure the intake of nutrients; 2, medication can eat some probiotics, if the stool is very thin, you can eat montelukast and so on to improve the stool properties of the drug; 3, to ensure that the child does not get dehydrated, no matter whether it is drinking oral rehydration salts, to give him some saline, or rice soup with some salt, also must ensure that not dehydrated, to have enough water. Or put some salt in the rice soup, but also must ensure that not dehydrated, to have enough water intake; 4, for a few children need anti-inflammatory drug treatment. So if the vomiting and diarrhea is very serious, you need to go to the hospital for timely treatment.