Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 15 years of experience. I look forward to working with you.
I am so sorry no expert responded to you overnight! AT this point how is Dudley doing? If he is still vomiting, especially if bloody, then this is an emergency situation and you must take him to your closest veterinary ER today. This may be far beyond worms; that is my top concern. Sometimes the worms are simply become apparent secondary to the vomiting since they live in the stomach/intestines. I worry primarily about a viral infection such as parvovirus or coronavirus (although if he is fully vaccinated through veterinarian with a series of vaccines, then unlikely to have parvovirus gastroenteritis). Sometimes worms can be the primary problem, though. I have seen puppies die from profound roundworm or hookworm infestations.
What is most concerning is that he is very small and he can become profoundly dehydrated. This in addition to the vomiting/diarrhea need to be treated today by a veteinrarian. I wish I had a wonderful at-home remedy for you but the problem is that whatever I recommend you give (there are not many over-the-counter great options but there are a few) will not stay down long enough to have an effect (he will vomit them back up). But, if you prefer some at-home suggestions I can make those. Recognize, this is not ideal and since this can become rapidly life threatening between dehydration and blood loss, I must recommend you have him seen right away.
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