Hello, I'm Dr. Kara. I have over 20 years of experience as a veterinarian and I'd like to help with your concerns about Omi's chronic troubles with diarrhea and stomach upset.
I am very glad to hear that her blood tests look normal.
I do believe that she has food allergies and she may have a primary intestinal disease as well. I think that she may have developed a sensitivity to the food that she was eating successfully for a while and that led to stomach upset which decreased her appetite and now diarrhea.
It will be important to describe what sort of loose stools she has to try and localize the problem. Loose stools with mucous or bright red blood point more towards large bowel diarrhea or colitis, whereas just watery stools with no mucous point more toward small bowel disease.
Chronic diarrhea does cause changes in motility of the gut and can lead to reflux and
vomiting. It can also lead to bacterial overgrowth in the gut. Probiotics such as Fortiflora or Benebac can help replace appropriate bacteria.
I know that she has had stool samples checked to make sure that parasites
aren't part of her problem in the past but have any been done recently? Have any other diagnostic tests been checked?
Has she had a fecal culture to check for abnormal bacteria such as clostridia?
Is she losing weight?
It is quite possible that she has a food allergy/sensitivity or inflammatory bowel
disease and that she needs a different low residue, easy to digest food or a
hypoallergenic food to be able to properly digest and absorb her food and not have loose stools. I highly recommend a trial of either Hills i/d or Purina Veterinary Diets EN. No treats, table food or edible chewies while she is on her food trial. If she does well she can eat these foods for life as they are balanced. Having had 2 dogs with inflammatory bowel disease I have a personal preference for Purina Veterinary Diets EN. Dogs with food allergies can benefit from Hills z/d or Purina Veterinary Diets HA.
Dogs with inflammatory bowel disease will worsen with stressful situations. There
may be times when she will need medications too, such as metronidazole or even
steroids if that is her problem, but I have found that a consistent, easy to digest diet is very helpful for long term control.
There are other possibilities too.
Addison's disease, which is a poorly functioning adrenal gland, can lead to chronic
diarrhea and vomiting. These dogs cannot handle stress at all because their adrenal gland doesn't produce cortisone when stressed and their electrolytes can be off too if their adrenal gland isn't controlling that normally either.
We see vomiting, diarrhea and sometimes physical collapse in severely affected dogs. Testing is an ACTH response test to check adrenal gland function and checking electrolyte levels. Treatment is steroid replacement therapy and electrolyte replacement.
Pancreatic insufficiency is another possibility. These dogs have a pancreas that produces a decreased amount of digestive enzymes, and the amount produced can wax and wane in some cases, especially early in the disease process. Testing is by
running a blood test called a TLI which checks for digestive enzymes. Treatment is replacement of digestive enzymes at each meal. An easier to digest food would be expected to create less problems with digestion and as such less diarrhea.
Kidney and liver disease can cause diarrhea too, but I because her blood tests were normal I doubt either of these would be the problem.
Because this has been a chronic problem for Omi then more diagnostics need to be done. They can be as simple as fecal checks and cultures, or they can be more invasive such as biopsies of her gastrointestinal tract to look for inflammatory bowel disease (which would be likely) or infiltrative cancers such as lymphoma (not likely at her age).
To try and settle her stomach today you can try either:
1) Pepcid-ac (famotidine) at one 10mg tablet per 20 to 40 pounds of body weight
every 12 hours.
2) Prilosec (omeprazole) at one 10mg tablet per 20 to 40 pounds of body weight
every 24 hours.
These will reduce stomach acid and should help if this is related to simple nausea and gastrointestinal irritation.
I would not feed her any food for 24 hours after the acid reducers are started. This should help stop gut spasms and restore normal gut motility. Small amounts of water or ice cubes given frequently are fine as he needs fluids after all that she has lost with diarrhea. You can give her pedialyte to replace electrolytes too but Gatorade is much too high in sugar which can make her intestinal irritation worse.
Today even with the fast you can start Kao-pectate at 1ml per pound or 1 tablespoon per 15 pounds of body weight every 6 to 8 hours. This is quite safe and will coat her irritated gi tract as well as absorbing bacterial toxins. You can use it for several days until her stools look normal. You can find kao-pectate at the drug store.
If she has a tense painful abdomen, continues to have diarrhea after being on kao pectate for 24 to 48 hours, becomes very lethargic, begins vomiting or runs a fever greater than 103.5F then she really must be seen by a veterinarian as soon as possible. Make sure to take a fresh stool sample with you when you go.
After her food fast start a bland diet of 1/3 boiled, lean hamburger (or white skinless chicken), all fats and juices drained off mixed with 2/3 boiled, plain white rice. Feed several small meals a day. You might wish to add 1 to 2 tablespoon(s) of canned pumpkin to each meal if you are seeing mucous in her stool as fiber helps soothe an irritated colon.
Once she feels better (no diarrhea for 48 hours) start mixing in what will be her
regular dog food very slowly, less bland more regular with each day. It should take a week or so to convert her back.
If Omi starts vomiting and feeling poorly though it would be best that she see a veterinarian now as anything you give her orally will just come back up worsening her dehydration.
Please let me know if you have any further questions.