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Why is my 5-week-old puppy vomiting and has diarrhea after new food?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed | Male | unneutered | 1 month and 4 days old | 2.6 lbs

I've been caring for six orphaned Dane X mastiff pups since they were six days old. They have been bottle fed divetelact puppy formula since then. They are now 5 weeks old and I've introduced tinned puppy mince this week and managed to get them to lap pedigree puppy milk however one pup seems to be vomitting quite a bit after eating/drinking and another seems to have diarrhoea.

1 Answer

Most Helpful Answer

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Answered By Jessica Desrosiers

Veterinary Technician

Published on November 10th, 2018

It's possible the change in food could be causing digestive upset. The best way to start transitioning to solids is to make a slurry of their regular milk replacer that they've already been on combined with a little bit of the puppy food. This helps make it easier to digest without being too big of a change and may help settle their stomachs. Checking for any parasites with a fecal exam and deworming may also help, however if the vomiting or diarrhea continues, a vet checkup to rule out anything more serious is best.

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