D-Limonene And Metaldehde Flashcards
What is an essential oil? And where are they found?
Naturally occurring volatile organic compound (VOC)
Found in leaves, seeds, bark, stems, roots, flowers, and other plants for fruit
What are the major uses of essential oils?
Food supplement/additive
Cleaning agent
Therapeutic
Pesticides
What is the most common exposure route of essential oils to pets?
Oral, dermal, or inhalation
What are the clinical signs of overexposure to essential oils?
Unsteady on feet Depression Low body temp Vomiting Diarrhea
D-limonene is a major constituent in essential from ??
Citrus fruit peel
Is D-limonene hydro/lipo-philic ?
Lipophilic
What are sources of exposure to D-limonene?
Botanical insecticide
Botanical herbicide
Biodegradable cleaning agents and solvents
What is the toxicity of D-limonene?
Generally concidered safe at 1-5%
Cats are more sensitive than dogs
T/F: D-limonene is a photosensitizer that readily oxidizes in air and sunlight, especially to sensitive skin, produces mild irritation or dermal sensitization
True
T/F: D-limonene is lipid soluble
True
=> readily absorbed through skin and GIT
-equally distributed in body between circulation and adipose tissue
What is the MOA of D-Limonene?
Unknown
-in rats, accumulates in proximal tubules cell-> nephrotoxic
What are clinical signs associated with D-limonene?
Ataxia, weakness, recumbency, paralysis
CNS depression, hypothermia, and hypotension
Smell like lemons
Mild to severe skin reaction
How do you treat D-limonene toxicity?
Decontaminate
Monitor temp
Fluids if needed
What is the prognosis of D-limonene toxicosis?
Excellent -sublethal toxicity (resolve in 6-12hrs)
Worse if rare skin rxn
What are the types of molluscicides?
Acetylcholinesterase inhibitors (OPs)
Metal salts- iron(III) phosphate, aluminum sulfate, and ferric sodium
Methiocarb
Metaldehyde
What is the most common molluscicide?
Metaldehyde
What are the properties of metaldehyde ?
Polymer of acetaldehyde
Highly flammable
Hydrophobic-poorly soluble in water
Short soil half-life (10-14days)- low potential for groundwater contamination
T/F: most poisoning’s by metaldehyde in cats and dogs are do to careless placement of bait
True
What are the exposure route of metaldehyde?
Inhalation (most toxic)
Ingestion of baits (intermediate toxic)
Dermal (least toxic)
Malicious poisoning of non-targeted animals
What is the oral LD50 of metaldehyde in dogs? And cats?
100mg/kg -dog
207mg/kg
Once ingested, what must occur to metaldehyde to be absorbed?
Acid hydrolysis -> acetaldehyde
Acetaldehyde and metaldehyde are both readily absorbed
T/F: metaldehyde crosses the BBB
True
Metabolism and excretion of metaldehyde?
aldehyde dehydrogenase converts acetaldehyde to CO2 -> exhaled
Enterohepatic recirculation
Urine
What is the MOA of metaldehyde?
Alters neurotransmitter concentrations and enzyme activities
- decreased brain GABA —> neuro stimulation
- increased monoamine oxidase —> decreased brain serotonin and norepi —> reduce threshold of convulsions
The increased neuro-muscular activity induced by metaldehyde can lead to what clinical conditions?
Metabolic acidosis (due to the production of acidic metaldehyde metabolites)
Hyperthermia (due to muscle contractions)
What are the clinical signs associated with acute metaldehyde? Toxicity
Acute neurological manifestations
Initial onset—>muscle tremor, salivation, anxiety, hyperestheisa, ataxia, tachycardia, and hyperthermia
Progression to acidosis—> vomiting, diarrhea, depression,and hyperpnea opisthotonos and tonic convulsions
Onset within 1-3hrs
Continuous seizures due to metaldehyde an lead to what??
CNS depression, and respiratory failure within 4-24hours
T/F: dogs and cats that recover from the acute phase of metaldehyde toxicosis may develop liver failure 2-3days after exposure
False
Only dogs, not cats
What lesions are associated with metaldehyde toxicity?
Formaldehyde ora acetaldehyde order in stomach (apple cider like odor)
Granules/bait in stomach
Petechia/ecchymosis in GIT mucosa
Congestion, edema, hemorrhage in lung, liver, and kidney
How can you diagnose metaldehyde toxicity?
History
Clinical signs
Stomach contents/odor
Lab analysis
What is the treatment for metaldehyde toxicity?
No antidote
Decontamination
- emetic
- gastric lavage
- activated charcoal
- enema
Fluid therapy for metabolic acidosis (sodium lactate)
Monitor for hyperthermia
Muscle relaxants -methocarbamol
Anticonvulsant - diazepam/phenobarbital
Horse—> xylazine and acepromazine
What is the prognosis for metaldehyde toxicity?
Good if they survive the first 24hrs
Full recovery takes 2-3weeks
Some post recover liver failure
