Friend, the symptoms and history you describe is consistent with a disease called Parvo virus. This is a very aggressive virus that affects the cells in the intestines, bone marrow and sometimes the heart of young puppies. The difficulty in treating parvo is keeping the puppy hydrated because of the constant vomiting/diarrhea. In addition, secondary bacterial infections that can occur. Could there be other possible causes? Yes, there are many other viruses, parasites or bacteria that can cause similar symptoms. But, the fact that other litter mates shared similar symptoms I would place parvo very high on the list of possible causes.
I understand that you have some financial constraints. But, this puppy needs to be treated by a veterinarian at least as an outpatient. Ideally she should be on IV fluids and no food or water orally until the vomiting is under control. But, if you can not afford for her to be hospitalized you can discuss with attending veterinarian about doing the following:
1- Teaching you how to give fluids under the skin to keep her hydrated.
2- Giving an injection of a long acting antibiotic (convenia).
3- You will give a strong anti nausea medicine (maropitant) injection under the skin once a day.
If you can do the above this will greatly increase the chances of survival for your puppy. Giving her things orally will cause her to vomit more and make things worst. If you can not have her seen by ER vet tonight to start her on the above plan then look into your local ASPCA or Shelter where they often offer veterinary services at a lower cost. In the meantime this is what you can do:
1- Start her on Pepcid AC (famotidine) 10mg 1/8th of a tablet every 12 hours. You can buy Pepcid AC over the counter in any pharmacy. Do Not give things like pepto bismol or imodium.
2- No food or water for the next 2-3 hours. Need to give her gastrointestinal tract time to rest.
3- After 2-3 hours offer a small amount of water. Wait half hour, if no vomiting, continue offering small amount of water every hour. In addition, give her a teaspoon of honey, pancake or karo syrup.
4- Follow up with a veterinarian as discussed above.
Note: If you are seeing her gums pale this further supports my above assessment. Highly recommend having her checked by ER vet.
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