Anticoagulant Rodenticide Flashcards
what are the two major groups?
coumarin derivatives
indandione derivatives
What examples of coumarin derivatives?
warfarin (first gen)
brodifocoum
difenacoum
bromadiolone
What are examples of indandione derivatives?
diphacinone chlorophacinone pindone (frist gen) valone (first gen)
Which generation anticoagulants are more toxic?
second gen (require single dose)
What is the absorption and distribution?
well absorbed (Rapid)
warfarin are highly protein bound (can be retained in non-active state for long time
what is the metabolism and excretion?
metabolized by oxidase enzymes and excreted into urine
warfarin has half life of 44h
- second gens have much longer half life
What is the MOA?
inhibit vit K epoxide reductase (more in second gen)
- rodenticide compete for common receptor
inhibits factor 10,9,7,2 (need vit K for activation)
How long after will you see decreased clotting times? bleeding?
prolonged clotting about 3d
bleeding 4-5d
What factors alter toxicity?
high fat diet (reduces bacterial vit K synthesis in GIT prolonged antibiotics protein binding (drugs will displace warfarin from binding protein) liver disease (less clotting factors) prolonged GIT disturbance (diarrhea = less vit K)
when are the clinical manifestations seen?
typically 3d till clotting factors are depleted
completely absorbed from stomach at 3-4d
what clinical signs are seen?
severe hemorrhage
sudden onset
epistaxis
dyspnea (laryngeal obstruction, blood in lungs, coughing)
anemia
melena
hematoma (ribs and joints)
rapid irregular heart beat
hemorrhage in brain (ataxia, paresis, convulsions)
abortion
proprioceptive deficits and a tender abdomen with second gen)
What is the Dx?
elevated coagulation time elevated prothrombin time elevated activated partial thromboplastin time normal platelet count normal white cell count reduced PCV thoracocentesis (blood aspirate, caution!!) chemical analysis of liver, blood, urine
what are the PM findings?
generalized hemorrhage
mild hepatic necrosis associated with hypoxia
what is the treatment
avoid trauma blood transfusion vit K1 - oral (for 4-5w) - 1 week is ok for wafarin Vit K3 - doesnt work cholestryramine - bile sequestration (reduces enterohepatic circulation)
