Friend, when there is blood in the stool with diarrhea it is a sign of inflammation in the colon (large intestines). This can be caused by many different medical conditions. It will be difficult for me to determine the exact underlying cause without a hands on examination and some testing. But, common causes are: Dietary indiscretion, ingestion of a foreign body, infections, parasites or even part of a systemic disease to name a few causes. Her eyes being hyperemic (red) could be a sign of a systemic disease or forceful vomiting. If her gums are dry this could be a sign of dehydration. If she is drinking more than usual this further supports the possibility of a systemic disease like: An infection, hormonal disorders, kidney or liver disease, etc.
In this case, I would recommend a hands on examination with family veterinarian, blood work, urinalysis and fecal analysis as initial screening test to determine the exact underlying cause. In addition she may need supportive care of IV fluids. In the meantime this is what you can do:
1- Do not give things like Pepto Bismol or imodium. You see, stopping the diarrhea with medication can make things worst if this is related to an infection or ingestion of a foreign body. In addition, pepto bismol will make the bleeding worst. Start her on Pepcid AC (famotidine) 10mg 1/2 tablet every 12 hours. You can buy pepcid ac over the counter in any pharmacy.
2- No food or water for 2-3 hours, need to give her gastrointestinal tract time to rest. Then, offer small amount of water followed by a diet of rice (75%) and boiled boneless chicken or ground beef (25%) until the stool is back to normal then wean her back into regular diet. Keep her indoors in a cool room and no exercise when fasting.
3- Supplement with a probiotic (fortiflora), these are friendly bacteria that help with regularity. You can buy this over the counter in any pet store.
4- Follow up with your family veterinarian for a hands on examination and blood work as discussed above. If cost is a concern look into your local ASPCA or Shelter where they often offer veterinary services at a lower cost.
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