Hello, my name is***** and I have over 20 years of experience as a veterinarian.
I understand that you are concerned that Balou ingested spoiled raw meatballs from the trash.
The two concerns here would be:
1) eating spoiled raw meat which can have high bacterial counts, like salmonella.
2) the other concern is that meat can be high in fat and rich, and if Balou isn't used to eating table food that can trigger a bout of pancreatitis and stomach upset.
If has been less than 2-3 hours since he has eaten this I think it's worth trying to get him to vomit it back up.
You can give him 1 tablespoon of 3% hydrogen peroxide per 10 pounds of body weight soaked up with bread chunks, or mixed with ice cream or a little food (no more than 3 tablespoons at a time even for a pup greater than 35 pounds).
Then take him outside and run him around to get the peroxide bubbling so he vomits.
If no vomiting in 10 minutes repeat the peroxide dose once.
If he vomits and seems to clear his stomach and be done I would check to see if most of the raw meat is present.
Once he clears his stomach to try and settle his stomach today you can give either:
1) Pepcid-ac (famotidine) at a dose of one 10mg tablet per 20 to 40 pounds of body weight every 12 hours.
2) Prilosec (omeprazole) at a dose of one 20mg tablet per 40 to 80 pounds of body weight every 24 hours.
These will reduce stomach acid and should help settle his stomach.
Then feed a homemade diet of 1/3 boiled, lean hamburger or boiled, white, skinless chicken, all fats and juices drained off the meat, and 2/3 boiled, plain, white rice.
If you don't have peroxide or he doesn't vomit you can get him to an emergency clinic to induce vomiting.
If it has been longer than 3 hours it is likely too late to induce vomiting.
At that point you can give him one of the acid reducers if he seems nauseous, and then just feed him the bland diet mix and watch him for signs of food poisoning.
If he starts vomiting in the next few days, has a tense painful belly or refuses to eat or runs a fever (more than 103F rectally) then that can signify food poisoning and he should be seen by a veterinarian immediately.
Please let me know if you have any further questions.