Hello, my name is***** and I'd like to help you and Patricia. Has she experienced any vomiting? Is she still eating for you?
If she is not vomiting and still has a good appetite, I would actually withhold food tonight (water is ok) and allow her tummy & colon to rest. You can give over the counter Pepcid AC (10 mg tablet by mouth every 12 hours) starting immediately. If she continues to do well, then start with a very bland diet (boiled rice, boiled chicken) and feed a small amount (1/4 cup). If she is no longer having diarrhea and eating well, you can continue the small amounts of rice and chicken for 48 hours. Then slowly transition back to regular food.
If she is vomiting, follow the same instructions to withhold food, giving a small amount in the morning. If she eats and does not vomit, great! I do not like for any dogs to vomit more than 24-48 hours without medical attention, so you may need an ER clinic if one is available.
A small amount of dark blood in the stool is common anytime the colon is irritated, so this could be something simple like she ate rabbit poo in the backyard to intestinal parasites to something much more serious that requires some blood work run. If this isn't resolving, be prepared for your vet to ask about running some tests
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