Welcome! My name isXXXXX am a 2003 graduate from UC Davis, and currently a Medical Director of a veterinary hospital.
I am sorry to hear about this concern for Max.
Yes, very concerning with no explanation.
The metronidazole is generally more for pets with diarrhea. Great for diarrhea, but not much for stomach issues or poor appetite.
You could ask your vet to prescribe some Mirtazapine, a appetite stimulant in dogs.
Also, he may be nauseated!
So, just in case:
To help settle the stomach you can use of the following, but not as a replacement for veterinary examination include
1.Pepcid A.C. (famotidine) comes in 10mg, 20mg, or 40mg tablets.
You can give it every 12 hours. You can give 0.5mg per pound of body weight. So, a 20 pound dog would get 10mg.
2.Prilosec (omeprazole). It comes in 10mg or 20mg tablets.
You can give in every 24 hours. You give 0.5mg per pound of body weight. So, a 20 pound dog would get 10mg
3.Zantac (Ranitidne). It comes in 75mg, 150mg, or 300mg sizes.
You can give it every 8 to 12 hours. You give 0.25 to 1mg per pound of body weight. So, a 20 pound dog would get roughly 1/3 tablet of the 75mg. Even with bigger pets, it is easiest to get the smallest size tablet. Even a 75 pound dog would only need one 75mg tablet.
Here is a bland diet recommendation:
Boiled boneless, skinless chicken breast OR low-fat cottage cheese
Cooked white rice
*Never add on salt, pepper, oils, butter to any of the above
*Ideally, give 1/3 chicken or cottage cheese, and 2/3 white rice
Lastly, if the vet has no clue and not suggesting other testing you need to demand they call a internal medicine specialist for help or simply transfer you to a specialist.Find Various Specialists
--> Under "specialty" select SAIM = Small Animal Internal Medicine
--> Or, you can search for a Neurologist, Cardiologist or Oncologist
I can't vouch that their interpretation of the x-rays is correct, so we must still be suspicious for gastrointestinal problems, and I woudl ask the vet about doing a blood test called a PLI to evaluate for pancreatitis.
Very sorry Max is not feeling well.
I hope that information has been helpful.
Please remember to select Reply to Expert, if for any reason you need further clarification, have more questions, or were expecting a different type of answer. Prior to leaving a feedback rating, which I greatly appreciate so I am recognized by Justanswer for responding, my goal is to provide you the best answer possible.