Friend, peanut butter is not toxic but because of the high fat content if consumed in large amounts it can cause: Vomiting, diarrhea, pancreatitis, etc. This is what you can try:
1- Do not give things like Pepto Bismol or imodium. Start her on Pepcid AC (famotidine) 10mg 1/8th of a 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 6-8 hours. Need to give her gastrointestinal tract time to rest. Keep her indoors in a cool room while fasting.
3- After 6-8 hours offer a small amount of water. Wait half hour, if no vomiting, offer 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 after doing the above she will need to be seen by a veterinarian for a hands on examination.
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