Kathie, the ointment antibiotic itself is not going to be life-threatening or systemically toxic, at worst this usually only causes mild gastrointestinal symptoms like vomiting or diarrhea. The main concern is the actual container if it becomes obstructed in the gastrointestinal tract. But, if she vomited the container then not likely for anything bad to happen. This is what you can recommend your sitter to do:
1- Do not give things like Pepto Bismol or Imodium. Start her on Pepcid AC (famotidine) 10mg tablet every 12 hours for the next 2-3 days. You can buy Pepcid AC over the counter in any pharmacy.
2- No food or water for 4-5 hours. Need to give her gastrointestinal tract time to rest.
3- After 4-5 hours offer a small amount of water. Wait half hour, if no vomiting, offer a small amount of rice (50%) and boiled boneless chicken or ground beef (50%) 4-6 times a day. Keep on this diet for several days then wean into regular diet.
4- If she continues to vomit or becomes lethargic, anorexic, painful abdomen, abdominal swelling, pale gums, etc. she should be seen by ER veterinarian to rule out an obstruction or perforation of the intestinal tract.
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