Anticoagulants, usually found in rat poison, are agents used to prevent the clotting of blood. These are considered as one of the most common household poisons. Anticoagulants block the synthesis of vitamin K which is essential for normal blood clotting. Absence of vitamin K results in spontaneous and uncontrolled bleeding.
A mild anticoagulant poisoning can usually be asymptomatic and can go undetected for several days, but as the poison begins to affect the system, the dog will become weak and pale due to blood loss. The bleeding may be external; this may be displayed as a nose bleed, bloody vomit, or bleeding from the rectum. Bleeding could also be in internal organs like chest or abdomen and can be fatal if it not treated timely.