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  • Rat bait is an anti-coagulant.  It works by preventing the formation of new clotting factors.  At the time your pet eats it, they have a normal amount of clotting factors in their blood.  But an active dog will use these all up, usually in about 2-3 days. Then they start to bleed.

  • The best scenario is that you saw them eat it and we get them to vomit it up, and treat with activated charcoal.  48 hours later we do a blood test to check their clotting is normal.  If not, we then need to treat for poisoning.

  • If a sufficient amount of rat bait is ingested and absorbed your pet will not form new clotting factors, and about 2-3 days later will start to bleed – anywhere and everywhere, depending on the bumps and scrapes of everyday life; into joints, into the abdomen, the chest, the brain, round the gums or eyes or mouth, or under the skin. Signs will be referable to where they bleed.

  • Sometimes you just see a quiet pale subdued dog.  Your vet may spot tiny little bruises under the skin on the tummy, on the gums or the whites of the eyes.  They may cough or bleed from the nose. The gums might be pale, the belly might be full, the breathing may be odd or there may be changes in their mental status. Sometimes we have no idea what the problem is, we take a blood test and where we draw the blood from bruises, resulting in a great big hematoma.

  • Once we suspect it, we will draw bloods to check the PCV or number of red cells in the blood.  If this is low we are worried.  We also check how quickly or slowly the blood will clot, and we will likely confirm this at the laboratory.

  • If your pet is critical they may need a plasma transfusion.  This doesn’t replace the red cells, it replaces the clotting factors.  This gives us the best ‘bang for buck’ to slow things down while we start treatment.

  • Next, we give Vitamin K.  The step in forming new clotting factors that rat bait interferes with, involves Vitamin K.  When we give Vitamin K we sidestep the problem, and the animal will form new clotting factors.  We might have to hospitalise and monitor them for the first 12 hours to make sure they don’t bleed critically before new clotting factors form. 

  • Because rat bait lasts in the body so long, we often must treat anywhere from 4-6 weeks with Vitamin K.  When we think it is safe, we stop the medication, and 48 hours later we blood test to see if the clotting time is normal. If not, we keep treating for another week or two then recheck.

  • Once we start treating with Vitamin K, we can’t do the test reliably.  So, if we treat straight away we are committed to at least 4 weeks of treatment which can be very expensive for large breed dogs.  So, the blood test usually makes sense.  Keep your dog very quiet and rested until after that 48-hour blood test in case you precipitate an early bleed by too much activity.

  • It helps us a great deal if you can bring the box from the rat bait in with you with even a rough idea of how much your pet may have eaten!!!

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