If too much time has passed and the pet has absorbed the medications or is already showing signs of poisoning, very aggressive therapy is needed and is not always successful. (suffieldvet.com)
Common signs of poisoning include signs of internal bleeding: lethargy, exercise intolerance, coughing, difficulty breathing (due to bleeding into the lungs), weakness, and pale gums. (petpoisonhelpline.com)
Like raisins and grapes, which are also toxic, the exact toxin and mechanism of action to cause signs of poisoning in some dogs are not known at this time. (thesprucepets.com)