& welcome, I am Dr. B, a licensed veterinarian and I would like to help you with your wee one today.
First, since your lass had has diarrhea few days before the blood appeared, it is most likely that we are looking at an upper GI based diarrhea bug that is now causing irritation and inflammation of the colon (which will be the source of the blood). Therefore, we need to address the cause of her diarrhea and will then likely see the blood and irritation to that lower bowel region settle.
Now as I am sure you can appreciate, just like people, cats can have diarrhea that is caused by a range of agents. In regards ***** ***** question regarding causes, common ones include bacteria viral, parasites (worms but also protozoa like Giardia, Coccidia, Tritrichomonas), toxins (less likely here hopefully), cancer (again hopefully less likely if she is only middle age), nutritional issues, and general dietary indiscretions. Of course some will be more prevalent in certain cat age groups. It can be daunting to get to the bottom of which differential is to blame, but since it sounds like she is otherwise normal and if the diarrhea is not profuse, there are a few things you can try at home try and get it to settle.
First, consider starting her on a light/easily digestible diet. Examples of this would be boiled chicken, boiled white fish, scrambled eggs (made with water and not milk), meat baby food (do avoid the ones with garlic powder in the ingredients) or there are also veterinary prescription diets that can be used in cases of gastroenteritis (ie Hill’s I/D or Royal Canin’s sensitivity). These diets aim nutrition to the stressed gut without making it work hard to digest the food. I would advise frequent small meals to minimize strain on the already stressed gut, and to help lower the volume of diarrhea.
As well, do keep a close eye on her water intake and her hydration. To check her hydration status to make sure she is not becoming dehydrated there are a few things we can test at home. One is whether the eyes appear sunken, if the gums are tacky instead of wet/moist, and whether the pet has a "skin tent" when you lift the skin. To see how to check these parameters , you can find a wee video on this HERE. ( They use a big dog but it makes it easier to see and the principles are exactly the same) If you are seeing any signs of dehydration already, then you do want to have your kitty seen by her vet before this gets out of control.
If you are concerned that she is becoming dehydrated from the fluid loss via diarrhea, you can try and encourage her to drink but offering fresh water or even low-sodium chicken broth. If she isn’t amenable to these, you can syringe feed pedialyte. Pedialyte is good here (though aim flavourless one since cats don’t love fruit) because it will get both fluids and lost electrolytes back into your kitty. A typical maintenance rate in an animal is 48mls per kilogram of weight a day. If you do give syringe pedialyte, this should obviously be divided up into multiple offerings through the day rather then all at once. This value will give you the total she needs day and is a good starting point to give you an idea of the feline daily requirement. (we aren’t calculating losses, so you can add an equivalent volume to match how much diarrhea is being producing). If she vomits when you have given pedialyte, then therapy should be discontinued (since we don’t want vomiting because of our intervention).
Further to this, if she isn't settling with a light diet alone then we can try a feline safe anti-diarrheals to slow things down gut. As I am sure you appreciate, these would not be a cure (since cures would depend on the culprit and might include antibiotics or anti-parasitics, etc.) but would slow the diarrhea to aid the body potentially absorb more water/nutrients then it would have if the diarrhea were unchecked. And giving some more form to her loose stools will help with her fecal control and decrease her accidents. In regards ***** ***** options , the one we most commonly use in cats is Kaolin (More Info/Dose) available from your local pharmacy or Protexin Pro-Fiber (which is available OTC at vet practices; example). Both will slow diarrhea safely cat and the Pro-Fiber has the bonus of providing support to the delicate good bacteria of the GI. And just to note, do avoid Pepto Bismol (as it contains aspirin) and Loperamide/Immodium (as this can cause sedation and adverse effects in cats).
I hope this information is helpful.
If you need any additional information, do not hesitate to ask!
All the best,
Thank you help