Welcome and thanks for asking your question. My name is***** am a licensed veterinarian. I am not set up to make a live call. But, I am happy to answer your question on this thread.
Friend, statin medications like Pravastatin have a very wide safety margin in dogs. A single dose of Pravastatin 40mg will not be life threatening to Saffy, at worst she may develop mild gastrointestinal symptoms like loose stool or vomiting otherwise she will be fine. If she does develop vomiting or/and loose stool this is what you can do:
1- Do not give things like Pepto Bismol or imodium. Start her on Pepcid AC (famotidine) 10mg 1/4 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 8-12 hours. Need to give her gastrointestinal tract time to rest.
3- After 8-12 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 your family veterinarian for a hands on examination.
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