Azithromycin is given by mouth or injection and is used on and off-label to treat a variety of infections. Give as directed. Common side effects include stomach upset. Do not use in pets that are sensitive to macrolide antibiotics. If a negative reaction occurs, please call your veterinary office.
Metronidazole is given by mouth or injection and is used off-label to treat certain anaerobic bacterial and protozoal infections and gastrointestinal conditions in dogs, cats, and other animals. Give as directed. Side effects may include nausea, vomiting, diarrhea, regurgitation, decreased appetite, tiredness, and drooling. Do not use in pets that are allergic to it, are debilitated, or are pregnant or nursing. If a negative reaction occurs, contact your veterinarian.