Exam 1 Flashcards
(285 cards)
1
Q
What type of toxic dose: The highest or largest dose which does not result in undesirable or toxic alterations
A
Highest nontoxic dose (HNTD)
1
Q
What is the prognosis of Naphthalene?
A
Reasonable if treated promptly
2
Q
Do organophosphates get distributed to the CNS?
A
Yes
2
Q
What are the natural pyrethrins?
A
Pyrethrin 1 & 2
Cinerin 1 & 2
Jasmolin 1 & 2
2
Q
Toxicity level of D-Limonene in cats at 5x recommended dose?
A
Mild toxicity
2
Q
What factors can decrease the toxicity of AR?
A
Pregnancy
Enzyme inducers (phenytoin)
2
Q
MOA of Bromethalin?
A
Uncoupling of oxidative phosphorylation
Lack of ATP
Insufficient energy for Na+/K+ pumps
3
Q
What can be done as symptomatic treatment for chlorinated hydrocarbon toxicity?
A
Diazepam or barbiturates for seizures
Oxygen, ventilation, fluids
3
Q
T/F: Younger animals are more sensitive to Cholecalciferol
A
True
4
Q
MOa of Ivermectin?
A
GABA agonist
5
Q
How does the soil half-life of chlorinated hydrocarbons compare to OPs?
A
LONGER
2-15 years (few weeks with OPs)
6
Q
What type of toxicity: The effect produced by daily exposure from one day to 30 days
A
Subacute toxicity
6
Q
What precipitate should be used to treat alkaloid poisoning?
A
Tannic acid
6
Q
What are the common routes by which organophosphates get into the body?
A
Oral (contaminated feed)
Dermal
Inhalation
7
Q
What does a nicotinic blockade from OP poisoning cause?
A
Paralysis
CNS depression
Coma
Dyspnea
Death (resp. failure)
8
Q
What are the most characteristic signs of Cholecalciferol?
A
Hematemesis and melena (GI)
PU/PD (renal)
Depression (neurologic)
9
Q
What is the antidote for apomorphine?
A
Naloxone
10
Q
What lesions are associated with Bromethalin?
A
Cerebral edema
Diffuse white matter vacuolization through CNS
11
Q
Which species has less plasma pseudocholinesterase?
A
Ruminants
11
Q
Dose for a harmless substance?
A
>15g/kg
11
Q
What is the cause of death in high exposure of OPs?
A
Respiratory failure (paralysis)
11
Q
In mammals, Rotenone is converted to what kind of metabolite?
A
Non-toxic metabolites
11
Q
What clinical signs are associated with Naphthalene?
A
Mothball breath
Hemolysis, heinz bodies, methemoglobinemia, seizures
Cataracts in neonates
11
Q
When i say Bromethalin, you say…
A
Neurotoxicant
12
What organ metabolizes calcidiol to calcitriol?
Kidney
13
What species is deficient in acetylating enzymes?
Dogs
13
Affect of charcoal broiled foods on enzymes?
Induction
14
What is the adsorbant of choice for toxins?
Activated charcoal
14
How is Ivermectin excreted?
Feces
15
What is the significance of the ABCB1 gene in dogs that receive Ivermectin?
Results in ~50x concentration of drug in the CNS
16
For feed, 100 g/ton = Xppm
110ppm
18
What type of toxicity: The effect produced by daily exposure for a period of 3 months or more
Chronic
19
This toxin can cause acute paralysis in dogs from topical exposure
Pyrethrins and Pyrethroids
19
Low doses of Nicotine can resemble what other toxicity?
OP/CM
20
Describe the atropine response test
Administer 0.02 mg/kg of atropine
If strong response, then less likely OP toxicity
Atropine treatment for OP toxicity is 0.1-0.5 mg/kg
20
High doses of Nicotine can resemble what type of drugs?
CNs depressants
20
What is the prognosis of Cholecalciferol?
Variable - the earlier treatment is started, the better
Severe hypercalcemia = more guarded
Hematemesis or mineralization = poorer prognosis
21
T/F: When treating for AR, you would test the Vitamin K even after it is discontinued
True
Check PT 24-48 hours after last dose of Vitamin K
22
The use of ipecac is contraindicated in what species?
Cats
23
What is the prognosis of Bromethalin?
Mild case - resolve over several weeks
Severe case - grave prognosis
24
How are dogs commonly poisoned with Ivermectin?
Overdose due to use of large animal products on small animals
Coming in contact with horse feces after treatment
26
Which biotransformation reaction is deficient in the neonate?
Conjugation
27
What drugs are examples of extensive first pass effect?
Lidocaine
Propranolol
Morphine
29
What drug has a strong affinity to kidney tissue?
Aminoglycosides
29
What nonspecific pathological lesions are associated with OP poisoning?
Pulmonary edema and congestion
Edema of various organs (including brain)
Necrosis in skeletal muscle
29
What levels of AChE activity are used to determine OP?
\<50% activity is suspicious
\<25% activity is diagnostic
29
Is Amitraz distributed to the CNS?
Yes
30
What is the acute oral LD50 of Amitraz for dogs?
~250mg/kg
Mild signs (sedation) seen in some dogs at 20mg/kg
32
What type of toxic dose: The lowest dose which produces toxic alterations and administering twice this dose will not cause death
Toxic dose low (TDL)
33
What is the most toxic of the Carbamates?
Aldicarb
Mimics the structure of ACh
34
What are xenobiotics?
Foreign chemicals that the body does not produce
Drugs and poisons are xenobiotics
35
Which reaction phase of biotransformation is the synthetic phase?
Phase 2
36
What is used to treat cerebral edema due to Bromethalin?
Mannitol +/- dexamethasone
37
What is the dose with no toxic signs called?
Maximum Tolerated Dose or Minimal Toxic Dose (MTD)
38
What is the most common biotransformation reaction?
Oxidation
39
What species is deficient in glucuronyl transferase?
Cats
39
What specific treatment is used for Naphthalene?
Ascorbic acid - converts MetHgb to Hgb
Methylene blue 1% - faster than ascorbic acid but is an oxidizer
40
What clinical signs are assocated with CNS stimulation following OP poisoning?
Anxiety
Restlessness
Hyperactivity
Tonic-colonic seizures (CNS depression in ruminants)
41
What species is most sensitive to OP induced delayed polyneuropathy?
Chickens
41
T/F: Chlorinated hydrocarbons are highly lipophilic
True
41
At what dose of nicotine do you see clinical signs in the dog?
1 mg/kg
42
Convert 1ppm to %
0.0001%
42
T/F: OPs are extensively metabolized in the liver
True
42
Clicker question:
If chelation therapy is recommended for a toxicant when levels reach 5mg%, will a blood level of 900mcg/dL require therapy?
No
42
What is used to treat ARs?
PO Vitamin K1 (phytonadione)
43
How long should you treat a patient with Warfarin poisoning?
1 week
44
What pathology is associated with delayed neurotoxicity following OP poisoning?
Degeneration and demyelination of peripheral and spinal motor neurons
44
Clicker question:
Which of the following factors has the shortest half-life?
A. II
B. VII
C. IX
D. X
B. VII
44
What is the half-life of Bromethalin in the rat?
5-6 days
46
What are the poorly perfused tissues?
Bone
Adipose tissue
47
How do the chemical properties of the metabolite differ from the drug?
Metabolite is more water soluble, polar, and ionized
48
Which organophosphates have direct acetylcholinesterase activity?
Dichlorvos
Monocrotophos
Trichlorfon
49
What toxin can cause abortion in cattle?
Anticoagulant Rodenticides from placental hemorrhage
50
What should you use in cats to induce emesis?
Xylazine
51
T/F: ARs are largely protein bound
True
51
What drugs should be avoided when treating Bromethalin?
Magnesium cathartics (CNS depressive)
52
What is the toxic component of Cholecalficerol?
Vitamin D3
54
What type of toxicity: The effect of a single dose of multiple doses during a 24 hour period
Acute toxicity
55
T/F: Pancreatitis has been reportedly found in some dogs with the more lipophilic compounds
True
56
How long does it take for clinical signs of AR to set in?
1-5 days
57
T/F: Compared to cholinesterases, chlorinated hydrocarbon toxicity will have less parasympathomimetic signs, and less severe CNS stimulation
False
Less parasympathomimetic signs, MORE severe CNS stimulation
57
What should you monitor when treating D-Limonene toxicity?
Temperature
Want to avoid hypothermia just as with Pyrethrins
59
Which species have high levels of oxidative enzymes?
Ruminants
Horses
59
MOA of DEET?
Unknown
Can cause surface irritation
60
Clicker question:
Which of the following insecticide toxicants would you expect to have the longest half-life?
A. OPs
B. CMs
C. Chlorinated hydrocarbons
D. Pyrethrins
C. Chlorinated hydrocarbons
61
Dose for a slightly toxic substance?
0.5g/kg
63
How do you calculate the standard safety margin?
Ratio between LD1 and ED99
64
What is the main clinical sign associated with chlorinated hydrocarbons?
CNS stimulation
65
What is the lowest canine lethal dose of Naphthalene?
~400mg/kg
One mothball can weigh 2.7-4g
67
How is toxicity expressed in mammals? Birds? Fish?
Mammals - LD50 in mg/kg body weight
Birds - LC50 in mg/kg feed
Fish - LC50 in mg/liter water
68
What type of toxic dose: Smaller to the highest nontoxic dose
Maximum tolerated dose or minimal toxic dose (MTD)
69
What is the prognosis of D-Limonene toxicity?
Exelent in sublethal toxicosis
Usually resolves within 6-12 hours
70
Are dogs or cats more sensitive to DEET?
Cats
71
What is the prognosis of Rotenone?
Generally good for mammals
Poor for fish and reptiles
72
What are our Chlorinated Hydrocarbons (Organochlorines)?
Diphenyl aliphatics (DDT, methoxychlor)
Aryl hydrocarbons (Lindane)
Cyclodienes (Aldrin, Toxaphene)
72
What are some lab findings of AR?
+/- anemia
Mild thrombocytopenia
Hypoproteinemia
73
Does Ivermectin cross the BBB?
Not typically
75
Dose for a moderately toxic substance?
\> 50-500mg/kg
77
What is the ratio between acute LD50 and chronic LD50?
Chronicity factor
78
T/F: Cats are more sensitive to D-Limonene than dogs
True
78
How long does it take for acute clinical signs or Bromethalin to set in (less common)?
2-24 hours
CNS excitatory signs
Usually with a supralethal dose
79
Clicker Question:
Which of the following aspects of toxicity are the same between OP and CM insecticides?
A. both toxicants undergo storage activation
B. both toxicants undergo lethal synthesis
C. cholinesterase activity can be tested for either
D. Pralidoxime is an effective treatment for either
C. cholinesterase activity can be tested for either
80
What drugs can cause the ABCB1 mutation?
Cyclosporine
Ketoconazole
Verapamil
81
Which species lacks oxidative enzymes?
Birds
81
MOA of OPs?
Irreversible inhibition of cholinesterases
Increase ACh at all cholinergic sites
82
What are our enzyme inducers?
Phenobarbital
Phenylbutazone
Griseofulvin
Rifampin
Chlorinated hydrocarbon insecticides
82
MOA of Naphthalene?
Oxidation products cause methemoglobinemia and hemolysis
Leads to tissue hypoxia
83
Clicker Question:
All of the following are general contraindications to inducing emesis after toxin ingestion EXCEPT:
A. patient is depressed/unconscious
B. patient is seizuring/high risk of seizures
C. known enterohepatic recirculation
D. known corrosive toxin
C. known enterohepatic recirculation
83
Clicker question:
Which of the following toxicants is primarily a CNS depressant?
A. Chlorinated hydrocarbon
B. CM
C. Amitraz
D. Pyrethrin
C. Amitraz
85
What drug can be effective in treating OP?
2-PAM
May not be efective against some OPs
May not be effective if "aging" has occurred (12-24 hours)
86
What is the point of adding Piperonyl butoxide of MGK-264 to PP?
Inhibits pyrethrin metabolism by insects
88
How long will it take to see clinical signs after OP poisoning?
15 minutes - 1 hour
89
What mammalian species is most effected by Rotenone?
Pigs
Highest toxicity in fish and cold-blooded animals
90
MOA of DDT-type chlorinated hydrocarbons
Slow Na+ influx and inhibit K+ efflux leading to partial depolarization
Causes repetitive firing of neuron - axonal hyperactivity
91
T/F: After treatment of AR, the patient is more sensitive to another exposure shortly after treatment
True
Lower toxic dose if repeated exposure within few weeks of treatment
92
What should be tested for direct detection of OP?
Stomach or rumen contents
Hair/skin with dermal exposure
93
What species is most sensitive to chlorinated hydrocarbons?
Cats
94
Is there a specific antidote for chlorinated hydrocarbon toxicity?
No
95
Are 1st or 2nd generation ARs more toxic?
Second
95
ARs: What treatment should be done when there are clinical signs, bleeding, PCV \<15%
Give clotting factors and RBCs
Vitamin K
Supportive care
97
When Cortisone undergoes biotransformation, what happens?
Inactive drug -\> active metabolite (Hydrocortisone/Cortisol)
97
What drugs can be used to treat seizures caused by PP toxicity?
Diazepam
Barbiturates
Propofol CRI
98
Nicotine is better absorbed in what pH environment?
Alkaline
100
T/F: Plant charcoal is more effective than animal charcoal?
True
102
How do you calculate the therapeutic index?
Ration between LD50 and ED50
The larger the value, the wider the safety margin
104
Charcoal is considered a universal antidote except for what two toxins?
Ammonia
Cyanide
105
Clicker Question:
Chlorinated hydrocarbons like DDt are highly lipophilic and excreted in the bile. This suggests that they likely undergo which of the following?
A. first-pass metabolism
B. lethal synthesis
C. enterohepatic recirculation
D. poor distribution into fat
C. enterohepatic recirculation
106
What are the moderately perfused tissues?
Muscle
Skin
107
How long should you treat a patient with AR poisoning but you dont know which one was ingested?
3-4 weeks
108
If a patient comes to your clinic and smells like lemons, what do you think could cause this?
D-Limonene
108
What clinical signs are associated with early stimulation of Nicotine?
Ataxia
Vomiting
Bradycardia
Tremors
Convulsions
108
What factors can predispose an animal to Cholecalciferol toxicity?
Renal disease
Hyperparathyroidism
High calcium/phos in diet
109
T/F: Dogs are more sensitive to PP than cats
False
Cats are more sensitive than dogs
110
What can be tested for Nicotine?
Urine
Stomach contents
Kidney
Liver
Blood
111
MOA of Amitraz?
Alpha-2 adrenergic agonist in the CNS
112
What is the most serious clinical sign associated with Amitraz?
Cardiovascular colapse and respiratory failure
113
What proetin do acidic drugs tend to bind to?
Albumin
115
Define a poison (toxicant)
Any substance when applied or introduced into the body may interfere with life processes or biological functions of the cells of the animal
116
What makes up phase 2 metabolic reactions?
Conjugation
117
What is the only microsomal conjugation reaction?
Glucuronidation
119
Describe the severity of PP
Generally acute, mild toxicity
121
What would you do to treat intermediate OP syndrome?
Supportive care
2-PAM may have benefit (nicotinic sites)
121
What will increase the toxicity of Amitraz?
Meperidine and sympathomimetic amines
Stress, debilitation, age, toy breeds
122
What precipitate should be used to treat lead poisoning?
Sulfate
123
T/F: There are no specific pathological lesions associated with chlorinated hydrocarbons
True
123
Clicker question:
If a patient presents with hypercalcemia and significantly elevated PTH, would Cholecalciferol be the top differential on your list?
No
124
MOA of Rotenone?
Blocks oxidative phosphorylation in the TCA cycle which prevents NADH from being oxadized to NAD and therefore interfering with production of ATP
126
What is the amount of chemical that can be ingested w/o causing deaths, illness or tixic alterations called?
No-effect level (Maximum nontoxic level)
127
What is the main clinical sign associated with ARs?
Hemorrhage
Signs depend on site of bleeding
129
What would you do to treat OP induced delayed polyneuropathy?
Symptomatic therapy only
131
T/F: Carbamates require bioactivation
Therefore more toxic than some OPs in very young patients
False
132
When I say Cholecalciferol, you say...
Hypercalcemia
133
What is the most common source of Naphthalene poisoning?
Mothballs
135
What are our enzyme inhibitors?
Chloramphenicol
Cimetidine
Ketoconazole
136
What condition may reduce the effect of Vitamin K1 in treating AR?
Liver failure
137
What clinical signs in dogs/cats are associated with DEET?
Basically CNS excitement signs:
Hypersalivation
Vomiting
hyperexcitability
Tremors
Ataxia
Seizures
138
MOA of D-Limonene?
Unknown (possible vasodilation)
139
The presence of alpha-cyano moiety has what effect on the metabolism?
Decreases the rate of hydrolysis
140
What are the primary targets of Bromethalin?
Brain and spinal cord
141
How is Bromethalin metabolized in the liver and what is the metabolite?
N-demethylation to desmethylbromethalin (more toxic)
143
Describe OP induced intermediate syndrome
Seen with massive doses, lipophilic agents, or more chronic exposure
No muscarinic signs or muscle fasciculations
145
What type of toxic dose: The amount of a chemical that can be ingested without causing any deaths, illness or toxic alterations in any of the anumals for the stated period (usually 90 days to two years or more depending on the species)
No-effect level (maximum nontoxic level)
146
What are the signs of OP induced delayed polyneuropathy?
Muscle weakness
Ataxia
Rear limb paralysis
147
Renal excretion of Nicotine is favored in what pH environment?
Acidic
148
MOA of Aryl hydrocarbons and Cyclodienes?
Na+ channel effects and also may inhibit GABA
150
Because Chlorinated hydrocarbons are highly lipophilic, what can this lead to?
Bioaccumulation in the food chain
151
Where in the body would you look for Rotenone for a diagnosis?
Stomach contents
Urine
Feces
Liver (postmortem)
152
The metabolite of what drug causes adrenal necrosis?
Midotane
Metabolite = O,P-DDD
153
What is the species order of sensitivity for ARs?
Pigs -\> dogs/cats -\> ruminants -\> horses -\> chickens
154
What toxin is toxic to fleas at all life stages?
D-Limonene
155
What are the plant sources for Rotenone?
Derris elliptica
Jicama seeds
155
What lesions are associated with Cholecalciferol?
Hemorrhagic gastroenteritis
Mineralization
156
What are the main tissue barriers?
Brain
Eye
Testicles
Placenta
Mammary gland
158
Where in the body can you find chlorinated hydrocarbons?
If insecticide is in blood, liver, or brain at significant concentrations
159
T/F: Second-generation ARs have short half-lives
False
Long half-lives
160
What plant is teratogenic to sows and cattle?
Nicotiana tabacum (Nicotine)
162
Clicker question:
What condition in canine patients is commonly treated with
O,P-DDD?
A. Hypoadrenocorticism (Addison's)
B. Pituitary dependent hyperadrenocorticism(Cushing's)
C. Overdose of exogenous corticosteroids
D. Primary pituitary hyperplasia
B. Cushing's
163
Clicker question:
If AR intoxication is suspected but you do not know what specific rodenticide was ingested. How long should you treat with vitamin K1?
A. 96 hours
B. 1 week
C. 10 days
D. 4 weeks
D. 4 weeks
165
What is the highest dose that does not result in undesirable/toxic effects called
Highest Nontoxic Dose (HNTD)
166
What is the elimination half-life of Amitraz and how long does it take to reach peak plasma concentrations?
~24 hours
Peak concentration after 5 hours
167
What clinical signs in rabbits/rats are associated with DEET?
Depression
Excitation
Ataxia
Tremors
Seizures
Coma
167
What is the main clinical sign associated with Ivermectin?
CNS depression
169
What is the most common conjugation reaction?
Glucuronic acid
171
What protein do basic drugs tend to bing to?
Acid alpha1-glycoproteins
Lipoproteins
172
MOA of PP?
Delay closure of sodium ion channels in the axonal membrane of the insect
May inhibit ATPase
Type 2 pyrethroids have a greater effect on sodium channels and interfere with GABA at high concentrations
173
What is the best way to enhance excretion of Nicotine?
IV fluids
Acidification of the urine
174
What are the highly perfused tissues?
Brain
Liver
Kidney
Endocrine glands
176
What is the prognosis of chlorinated hydrocarbon toxicity?
Guarded to good depending on dose and early detoxification
177
When diagnosing DEET, what level is considered diagnostic?
20ppm
178
How do you treat CM toxicity?
Atropine just like for OPs
179
What lab changes will you see with Cholecalciferol?
Hypercalcemia, hyperphosphatemia
Elevated calcidiol and calcitriol
Decreased PTH
180
What is the prognosis of DEET?
If sublethal exposure, usually respond in 24-72 hours
181
Which organophosphate has more significant tissue accumulation?
Dichlorvos because it is more lipophilic
181
What are the synthetic pyrethrins?
First generation (type 1) do not contain an alpha-cyano moiety
Second generation (type 2) do contain the alpha-cyano moeity which increases their insecticidal potency
182
What type of exposure is most common with PP?
Dermal
Ingestion and inhalation are possible too
183
What clinical signs will you see later on after Nicotine exposure?
CNS depression
Tachycardia
Paralysis of respiratory muscles causing death
184
ARs: What treatment should be done for very recent exposure and normal coag panel?
Decontamination (emesis, activated charcoal)
Start Vitamin K to be safe
185
What drug is used to treat muscle tremors caused by PP toxicity?
Methocarbamol
187
What drug is contraindicated with Carbaryl poisoning (CM)?
2-PAM
Can potentially increase the carbamylation process
188
Which species is deficient in sulfate conjugating enzymes?
Pigs
190
What effect does grapefruit have on enzymes?
Inhibitor
192
What is the lowest dose which produces toic alterations and administering 2x this dose will NOT cause death called?
Toxic Dose LOW (TDL)
193
Clicker question:
Which of the following is not one of the vitamin K dependent factors?
A. II
B. VI
C. IX
D. X
B. VI
194
How long will ARs persist in the environment?
Weeks to months
196
Which species has low levels of drug metabolizing enzymes?
Fish
197
What is used to treat seizures/tremors due to Bromethalin?
Diazepam, phenobarbital
198
What electrolytes are lost because of Cholecalciferol?
Sodium and potassium
199
What happens when Rotenone comes into contact with nerve axons?
Anesthetic effect
201
What is the most common clinical sign associated with Amitraz?
Sedation lasting 24-72 hours
202
With ARs, what species can be poisoned by relay toxicosis?
Swine, dogs, and cats
203
Which has a faster onset and shorter duration of action? OPs or Carmabates
Carbamates
204
What % hydrogen peroxide should be used to induce emesis?
3%
206
T/F: Pyrethrins bind more strongly at lower temperatures
True
207
Dose for an extremely toxic substance?
≤ 1mg/kg
208
Chemical composition of metabolite conjugates?
Inactive
Water soluble
209
What is the prognosis of Ivermectin?
Depends on exposure and ability to pay for care
Generally no long-term sequelae if they survive
210
What are the most commonly used diuretics?
mannitol
Furosemide
211
What type of toxic dose: The dose which produces toxic alterations and administering twice this dose will result in death
Toxic high dose (THD)
212
Clicker question:
What is the MOA of the organochlorine toxicants?
A. Alteration of neuronal sodium channels
B. Increased release of GABA
C. Reversible inhibition of AChE
D. Acute cerebral edema
A. Alteration of neuronal sodium channels
213
What is it called when OPs that require desulfuration are activated by liver metabolism?
Lethal synthesis
Less toxic to youn patients
More toxic if enzyme inducers are present
214
What organ metabolizes Cholecalciferol to calcidiol?
Liver
215
How is Bromethalin excreted?
Mainly in bile
Small amount in urine
216
What is the prognosis of AR?
Generally treatable depending on where hemorrhage has occurred
218
What is the prognosis of Amitraz?
Pretty good
219
The RBCs of what species are more susceptible to oxidative injury?
Cats
220
T/F: Bromethalin is effective against warfarin-resistant rodents
True
221
What trype of enzymes can enzyme inducers induce?
Microsomal
222
What is the dose which produces toxic alterations and administering 2x this dose WILL cause death called?
Toxic Dose HIGH (TDH)
223
What drugs should be avoided in the treatment of OP?
Phenothiazines
Aminoglycosides
muscle relaxants
Drugs that depress respiration (opioids)
225
What are the predominant clinical signs of Rotenone?
Depression and convulsions
227
What type of toxicity: The effect of exposure drom 30 days to 90 days
Subchronic toxicity
228
What precipitate should be used to treat oxalate poisoning?
Calcium
228
Which of the following blood products would you use for a hemorrhaging AR patient?
A. Fresh frozen plasma
B. Frozen plasma
C. Fresh whole blood
D. Stored whole blood
E. Cryoprecipitate
F. Platelet-rich plasma
A,C,E
229
What is "storage activation" and which organophosphates are subject to it?
If sealed and stored 1-2 years, it is more toxic
Parathion
Malathion
Diazinon
Coumaphos
230
MOA of Caholecalciferol?
Causes hypercalcemia and hyperphosphatemia
Increased GI absorption and decreased renal excretion of Ca2+
231
How long after exposure to OP does OP induced delayed polyneuropathy occur?
10-14 days
232
What should be avoided when treating DEET?
Magnesium cathartics (may cause CNS depression)
233
MOA of CMs?
Reversible inhibition of AChE
AChE can hydrolyze CMs but at a slower rate than ACh (~15-30 minutes compared to ~150 microseconds
234
When Parathion undergoes biotransformation, what happens?
Nontoxic drug -\> toxic metabolite (Paroxon)
235
Toxicity level of D-Limonene in cats at 15x recommended dose?
Severe toxicity lasting for 5 hours
237
Clicker question:
If you wanted to use Ivomec® extra-label and you know that toxicity can be seen at doses as low as 300mcg for a 1kg kitten, how many milliliters of undiluted (1%) Ivomec® would that be?
A. 0.003mL
B. 0.03mL
C. 0.3mL
D. 3mL
B. 0.03mL
238
In fish and insects, Rotenone is converted to what type of metabolite?
Highly toxic metabolites
239
Which organophosphates have no acetylcholinesterase activity and must be desulfurated before they become active?
Bromophos
Diazinon
Fenthion
Parathion
240
What is the only fluid that you do not freeze for sample collection?
Whole blood - refrigerate it!!!
241
When Aspirin undergoes biotransformation, what happens?
Active drug -\> active metabolite (Salicylic acid)
243
What drugs should be avoided when treating Nicotine toxicity?
Antacids (which would increase absorption and reduce excretion)
244
T/F: As a result of bioinactivation, most drugs are bioinactivated or detoxified
True
245
What species is deficient in hydroxylation and dealkylation?
Cats
245
What tissue acts as a "sink" for chlorinated hydrocarbons?
Fat
Half-life can be weeks to months
Weight loss can disrupt equilibrium
247
1ppm = what mg/kg?
1mg/kg
248
T/F: Inhalation of Rotenone is more toxic than ingestion
True
250
How long does it take for ARs to reach peak blood level?
6-12 hours
251
What do you do to treat Cholecalciferol?
Treat the hypercalcemia
252
Is there a specific antidote for Amitraz?
Yes
Atipamezole (better) or Yohimbine
253
How is Cholecalciferol excreted from the body?
Mainly in bile/feces
254
MOA of ARs?
Inhibit vitamin K epoxide reductase
Reduces vitamin K precursors
Second-generation are more potent than first-generation
255
Clicker question:
Which of the following tests is most appropriate for follow-up monitoring of a patient who has been treated for AR toxicosis?
A. PIVKA
B. PT
C. PTT
D. ACT
B. PT
257
What factors can enhance AR toxicity?
Vitamin K deficiency
Liver disease
Enzyme inhibitors (cimetidine)
Trauma, surgery
258
T/F: Nicotine stimulates the CRTZ
True
259
How long does it take for clinical signs of Cholecalciferol to appear?
24-36 hours
261
ARs: What treatment should be done when there are clinical signs, bleeding, but PCV \> 15-20% and stable?
Vitamin K
Clotting factors (FFP, cryoprecipitate)
Consider giving RBCs (fresh whole blood)
262
How long should you treat a patient with Brodifacoum poisoning?
4 weeks
263
Which of the coagulation parameters is the first to be affected by ARs?
1. PIVKA
2. PT
3. PTT (when 70% gone)
4. ACT (when 95% gone)
264
How much more sensitive are insect sodium channels than mammalian ones?
1000x
265
Dose for a highly toxic substance?
1-50mg/kg
266
Administration of sodium bicarbonate will enhance the excretion of what drugs?
Weak acids
Ex: NSAIDs, phenobarbital
267
How long does it take for subacute clinical signs to set in (more common)?
2-3 days, progress over 1-2 weeks
CNS depression
268
What is it important to monitor when treating PP toxicity?
Temperature
Hypothermia can prolong clinical signs
269
What drug is commonly trapped by the thyroid gland?
Iodine
270
What makes up phase 1 of metabolic reactions?
Oxidation
Reduction
Hydrolysis
271
T/F: Ipecac increases the effectiveness of activated charcoal?
False
Decreases the effectiveness
272
What is the prognosis of PP toxicity?
Generally very good
273
Clicker question:
Which of the following findings would make you the least worried about the risk of renal failure?
A. Hematuria
B. Hemoglobinuria
C. Myoglobinuria
A. Hematuria
274
What are other possible DDx of Amitraz?
CNS depressants
Ethanol
Ivermectin
Ethylene glycol
Marijuana
275
What is the elimination half-life of Ivermectin?
~2 days
276
When I say Anticoagulant Rodenticides, you say...
Bleeding
277
Dose for a practically nontoxic substance?
\> 5-15g/kg
278
What species is resistant to Bromethalin and why?
Guinea pigs because they lack the correct metabolic enzymes
279
How long after dermal exposure to D-Limonene does it take to reach maximal blood concentration?
10 minutes
280
What drug has a strong affinity to calcium in skeletal tissues?
Tetracycline
281
Administration of ammonium chloride or methionine enhance the excretion of what drugs?
Weak bases
Ex: alkaloids, amphetamines
282
T/F: CNS stimulants may increase the toxicity of DEET
False
CNS depressants
283
What clinical signs are associated with nicotinic stimulation from OP poisoning?
Muscle fasciculation
Tremors
Twitching
Spasm
Hypertonicity
Stiff gait
284
ARs: What treatment should be done when there are no clinical signs but prolonged coags?
Vitamin K
Consider giving clotting factors (FFP, cryoprecipitate)
285
What does Nicotine mimic at low doses?
ACh
