Toxicoses & Food Animal Antidotes

Toxicoses & Food Animal Antidotes ACVPM 2007 Study Group Dawn Fitzhugh

Toxicoses • Xylitol • Micotil

Xylitol Toxicosis • What is xylitol • A natural, sugar-free sweetener • AKA a sugar alcohol • Found in toothpaste, baked goods, gums, candies • History: • Beginning in 2002, APCC began getting calls of xylitol toxicosis in dogs. Xylitol is new to the US market.

Xylitol • Clinical Signs: • Vomiting, lethargy, hx of eating something • Ataxia, seizures • Petechia, ecchymosis, bloody stool • Diagnosis • Check BG. Xylitol triggers insulin release and leads to hypoglycemia in dogs. Also hypokalemia • Check liver enzymes. Causes acute hepatic necrosis • Check clotting times/coag panel/platelet count. Leads to coagulopathies (bc of liver failure)

Xylitol • Treatment (do if >0.1grams/kg) • Induce vomiting if possible • Administer dextrose • Begin IV fluids • Plasma transfusion • Hepatic protectants: silybin, n-acetylcysteine, S-adenosyl-L-methionine • DDx of acute hepatic necrosis: • Acetaminophen • Hepato-toxic mushrooms • Aflatoxins • Iron • Blue-green algae • Infectious causes: Hepatitis virus, lepto, mycoses, toxoplasma

Xylitol Reference • Acute hepatic failure and coagulopathy associated with xylitol ingestion in eight dogs • Eric K. Dunayer, Sharon M. Gwaltney-Brant • JAVMA 1 Oct 2006

Micotil • Aka tilmicosin • A macrolide antibiotic • Used as injection in cattle to tx or prophylaxis for resp dz assoc with • Mannheimia (Pasteurella) hemolytica • Positive chronotrope, negative inotrope • Any exposure warrants evaluation

Micotil • Adverse effects: • Heart rate changes • Feeling hot or flushing • Nausea, dizziness, weakness, vomiting • Death possible • Treatment • Don’t use B-andronergic antagonists or epi • Dobutamine or dopamine may be helpful

Micotil • Prevention • Sharps awareness • Limit injections to less than 2 mLs in trigger pull, multiuse syringes

Food Animal Antidotes • FARAD: Food animal residue avoidance database • WDI: withdrawal interval • WDT: withdrawal time • AMDUCA: animal medicinal drug use clarification act • NADA: new animal drug approval, a #

Antidotes for Food Animals (FA) • Not readily available because • Restrictions on compounding • Limited market, not financially wise • If an antidote must be used in a FA • Contact FARAD for recommended WDI

Unapproved Antidotes w/ Vet Label • Atropine sulfate • To treat organophosphate toxicity in cattle, sheep, horses • Organophosphates are cholinesterase inhibitors • 3 D milk, 14 D meat WDI • Vitamin K1 aka phytonadione • To tx sweet clover toxicosis, rodenticide tox, sulfaquinoxalone • No WDI required • Epinephrine: no WDI

Human-Approved Antidotes • Pralidoxime chloride (2-PAM) • Adjunct to atropine in tx of OP tox • Contraindicated in tx of carbamate tox • Repeated dosing req’d • 6 D milk 28 D meat WDI • Dimercaprol aka British anti-lewisite (BAL) • Arsenic, lead, mercury toxicoses bc complexes heavy metals • Repeated dosing req’d • 5 D withdrawal time

Compounded antidotes • AMDUCA permits compounding from approved human or animal drugs under certain conditions but NOT compounding from bulk drugs! • Compounding from bulk drugs is ILLEGAL under FDA laws and regs • Compliance Policy Guide (CPG) of the FDA does allow some common sense

CPG Factors for Regulatory Action • Health of animals threatened or suffering or death would have resulted from lack of tx • Valid vet-client-patient relationship req’d • Milk or meat residues caused by compounding (vet must prescribe extended WDI) • Approved human or animal drug that could have been used extralabel

Toxicoses & Food Animal Antidotes