Pharm I Final Exam Flashcards

1
Q

Dantrolene is a _________-receptor antagonist

A

Dantrolene is a ryanodine-receptor antagonist

It inhibits Ca2+ release from the sarcoplasmic reticulum, resulting in muscle relaxation

Dantrolene is the drug of choice for treatment of malignant hyperthermia

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1
Q

Which inhalant anesthetic has the lowest blood/gas coefficient?

What does that mean?

A

Desflurane

Desflurane has a blood/gas coefficient of 0.45, so at equilibrium the concentration dissolved in blood will only be 0.45 times that in the alveolus.

The more insoluble the agent (lower blood/gas coefficient), the faster it will reach equilibrium

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1
Q

What is the term used for the equilibrium concentration of an anesthetic in the alveolus that is required to prevent movement and response to pain in 50% of individuals?

A

Minimum Alveolar Concentration (MAC)

MAC will vary between differerent drugs, and between different species for the same drug

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2
Q

What drug reverses the effects of competitive neuromuscular blockers and treats myasthenia gravis?

A

Neostigmine

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2
Q

What is the primary clinical use for phenobarbital?

A

anti-epileptic drug

Occasionally it is used as a sedative

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3
Q

Which of the following might you use to induce anesthesia in a patient with significant cardiac disease?

  • A. Thiopental
  • B. Propofol
  • C. Alfaxalone
  • D. Ketamine
  • E. Etomidate
A

Etomidate

Etomidate works very similarly to propofol and alfaxan but with fewer CV effects

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3
Q

Buprenorphine, a partial µ-agonist, is commonly administered submucosally in which animal?

A

Cats

Buprenorphine has a long duration (up to 8 hours) in cats. It is popular for use in cats because less dysphoria/excitement is seen compared to other opioids, and the buccal administration and less frequent dosing are convenient

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4
Q

Which of the following CNS depressant drugs are used to stimulate appetite in cats and dogs?

  • phenothiazines
  • butyrophenones
  • benzodiazepines
  • a2adrenergic agonists
  • opioid agonists
A

benzodiazepines

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4
Q

T/F: Acepromazine may reduce catecholamine-induced cardiac arrhythmias

A

True

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5
Q

Acetaminophen is sometimes seen as a cause of poisoning, particularly in which animal species?

A

Cats

Acetaminophen produces toxic metabolites, particularly in cats. These toxic metabolites are usually mopped up by glutathione, but liver glutathione reserves can be quickly used up and methemoglobinemia and liver damage may result.

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5
Q

Why is Bromide typically avoided in cats?

A

Bromide is less effective in cats than it is in dogs and makes ~50% of cats cough, which can lead to irreversible lung damage and death

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6
Q

Loperamide is used clinically for what purpose?

A

Loperamide is used as an anti-diarrheal

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7
Q

Which inhalant anesthetic is most likely to trigger malignant hyperthermia [MH]?

What drug would you use to treat MH?

A

Halothane

All inhalant anesthetics can trigger malignant hyperthermia (MH), btu halothane is most likely to do so. Dantrolene is used to treat MH.

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8
Q

What is the mechanism of action for dissociative agents?

A

NMDA receptor blockade

Remember, dissociative anesthesia is characterized by catalepsy, amnesia, and anesthesia without necessarily having complete unconsciousness

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8
Q

T/F: Dogs are the most sensitive species to Xylazine, followed by cats, ruminants, then horses

A

False.

Ruminants are most susceptible to Xylazine. Then dogs/cats/horses, then swine.

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8
Q

What is the only inhalant anesthetic that provides analgesia?

A

Nitrous Oxide

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9
Q

Give an example of an opioid drug that is metabolized via extra-hepatic pathways

A

Remifentanil

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10
Q

You performed a necropsy on a patient. Previously the patient had been diagnosed with feline hyperthyroidism. Your patient’s heart is on the right, with the yellow arrows.

What is the condition called?

What could you have given this patient to prevent this condition from occurring?

A

Myocardial hypertrophy

Propanolol is used in cases of feline hyperthyroidism to prevent myocardial hypertrophy

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11
Q

T/F: A drug’s volume of distribution (Vd) is a good indication for the ability of drug to diffuse across membranes

A

True

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12
Q

All of the following statements about pharmacokinetics of barbiturates are true except:

  • They are administered intravenously and orally
  • Duration of action depends on redistribution and elimination
  • They are metabolized by hydroxylation in the liver
  • They are enzyme inducers
  • Acidification of urine enhances renal excretion
A

Acidification of urine enhances renal excretion

In real life: renal excretion of barbiturates is enhanced by alkalinization of the urine.

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12
Q

What is Etomidate’s effect on intracranial pressure

A

Etomidate decreases intracranial (and intraocular) pressure

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12
Q

Name 2 drugs that are used to reverse the effects of Xylazine

A

Tolazoline and Yohimbine

Both are alpha-2 antagonists used to reverse the effects of Xylazine (alpha-2 agonist)

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13
Q

Why is glycopyrrolate given as a pre-anesthetic rather than atropine?

A

Glycopyrrolate is more specific to the heart and causes less tachyarrhythmia than atropine

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14
Q

Which inhalant anesthetic drug is considered the most potent cerebral vasodilator?

A

Halothane

Increases intracranial pressure!!

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15
T/F: Phenothiazines can have anti-emetic effects
**True!** Remember that apomorphine causes emesis by stimulating dopamine receptors in the CRTZ, *so by blocking dopamine in the CRTZ, phenothiazines can have an anti-emetic effect*
16
Which of the inhalation anesthetics that we've discussed has the fastest induction?
**Desflurane**
16
What is the drug of choice for treatment of malignant hyperthermia?
**Dantrolene**
17
Which species is more sensitive to dose-dependent hemolysis with **Guaifenesin**: horses or cattle?
**Cattle are more sensitive to dose-dependent hemolysis with Guaifenesin** Concentrations higher than 5% can cause hemolysis in cattle. Concentration higher than 10% can cause hemolysis in horses.
19
Phenothiazine derivatives cause CNS depression mainly by:
Blocking dopamine receptors in the CNS
20
Which is the best choice to treat urinary incontinence in a spayed bitch? * Antibiotics * Bethenachol * Phenylpropanolamine * Pralidoxime * None of the above
**Phenylpropanolamine**
21
Muscarinic receptors are SLOW and involve smooth m. contraction and glandular secretions. What type of receptors are these? * Ionotropic * Metabotropic * Nuclear * Kinase-coupled * Indirect
**Metabotropic**
21
Which inhalant anesthetic drug is considered most likely to cause catecholamine-induced cardiac arrhythmias?
**Halothane** Halothane affects sensitivity of the heart to catecholamines
22
Morphine is popularly combined with __________ for epidurals
Morphine is popularly combined with **_bupivacaine_** for epidurals
23
**Diazepam** should not be used IM due to its pain on injection and poor IM absorption. Which other benzodiazepine could be given IM instead?
**Midazolam**
24
a2 agonist drugs are especially useful for treatment of pulmonary edema in sheep
**No, that's not right at all** *Caution should be taken when using a2 agonist drugs in sheep, as you may see several effects on the lungs leading to pulmonary edema*!!
25
Which drug that we've discussed in class is considered the least selective alpha-2 agonist?
**Xylazine** Xylazine has a 160:1 Alpha-2:Alpha-1 ratio. Compare this to the most selective (Dexmedetomidine) with a 1600:1 ratio
26
Which of the drugs that we discussed in class is the most arrythmogenic inhalant anesthetic?
**Halothane**
28
T/F: Nitrous oxide is a potent muscle relaxer
**False** Nitrous oxide induces very poor muscle relaxation
29
\_\_\_\_\_\_\_\_\_\_\_\_ causes irreversible inhibition of COX by acetylating its active site
**Aspirin (acetylsalicylic acid)**
29
In an emergency: In dogs, cats, and foals, what dose of **Diazepam** may be given IV to effect?
**5-10 mg doses** 5-10 mg doses of Diazepam IV may be given to effect. This should stop the seizures for up to 20 minutes and give time for assessment. *Diazepam is safe when given IV*
30
T/F: Methohexital is a barbiturate
**True**, good job! Not currently available in North America; used to be used in sighthounds in place of Thiopental
32
T/F: Facilitated diffusion of drugs is a carrier-mediated transport that requires energy
**False** Facilitated diffusion of drugs is a carrier-mediated transport, **_but does not require energy_**
33
Why is **Etomidate** not used as a CRI?
**adrenocortical suppression** and **propylene glycol ** Mostly because Etomidate causes transient suppression of adrenal steroid production, which precludes CRI dosing *or* use in patients with hypoadrenocorticism
34
Which of the following drugs is the drug of choice for treatment of acute bronchial asthma? * isoproterenol * epinephrine * ephedrine * albuterol * ipratropium
**albuterol** Albuterol is a direct acting β2 agonist
35
The antithrombotic effect of aspirin is **mainly** due to:
inhibition of platelet aggregation
36
Which of the following is false regarding NSAIDS? * Block cyclooxygenase enzymes * Highly bound to plasma proteins * Penetrates CNS, but not found in milk * More potent anti-inflammatory drugs than corticosteroids
More potent anti-inflammatory drugs than corticosteroids
36
#1 local anesthetic for Breyer's Block?
**Prilocaine**
36
What is the name of the preservative associated with **Halothane** that can build up in vaporizers and throw off their calibration?
**Thymol**
37
Why is **Telazol® **not commonly used in small animal anesthesia?
Telazol® is a combination of tiletamine (dissociative) and zolazepam (a benzodiazepine). Dogs metabolize the zolazepam more rapidly than the tiletamine, which can lead to a rocky recovery (muscle rigidity, delerium, etc...)
38
In which breed of dog do we see a very prolonged effect with thiobarbiturates due to a deficiency in certain metabolic enzymes?
**Greyhounds** Thiobarbiturates are typically metabolized by hydroxylation in the liver. Greyhounds are deficient in required enzymes, and we therefore observe a prolonged effect
39
All of the following are adverse effects associated with Acepromazine except: * Hypothermia * Bradycardia * Hypertension * Possible lowering of seizure threshold
**Hypertension**
40
T/F: Though inhalant anesthetics cross the blood-brain barrier, most of them do not cross the placenta
**False** Inhalant anesthetic drugs cross the blood-brain barrier **_AND they cross the placenta_**
42
Which of the following anticonvulsant drugs is the **most** **effective** in the long-term treatment of hereditary siezures in dogs and cats and is relatively safe? * phenytoin * diazepam * potassium bromide * phenobarbital * primidone
**phenobarbital**
43
Which species is considered to be most sensitive to **Procaine**?
**Horses** Procaine is a local anesthetic that is designed to be given IM. If this drug is introduced into a blood vessel, convulsions may be seen
44
Which drugs are involved in the **MLK Drip**? What is the therapeutic use of the drip?
**_M_**orphine, **_K_**etamine, **_L_**idocaine MLK drip is given as a CRI for analgesia
46
Which of the following is widely used as a potent anti-tussive? * Morphine * Codeine * Methadone * Hydrocodone
**Hydrocodone**
46
What is the effect of **propofol** on intracranial pressure?
**Propofol decreases intracranial and ocular pressures** This makes it useful for patients with CNS disease
46
Which anesthetic inhalant can react with soda lime adsorbent (used to collet CO2) and cause *formation of **Compound A***, a potential nephrotoxin?
**Sevoflurane**
47
Which drug would you use for reversal of opioid-induced respiratory and/or CNS depression in dogs who have received a full µ agonist?
**Naloxone** Note that it is not 'routine' to reverse opioids in the way that you might reverse an a2 agonist. *Naloxone is typically only used if there is a problem!* It has a short duration of action (1-2 hours), so repeated dosing may be necessary if the original µ agonist is longer acting.
47
T/F: Opioids generally should be avoided in cases where increases in intracranial pressure are contraindicated
**True** You may see increased intracranial pressure (ICP) with opioids due to cerebral vasodilation (especially if the CO2 levels are rising due to decreased respiratory drive)
48
What adverse affect might we see with oral administration of **diazepam** to a cat?
**hepatotoxicity / hepatic necrosis** (Other benzodiazepines have not demonstrated this issue, nor has injectable diazepam)
49
What is the mechanism of action for **barbiturates**?
**Barbiturates act by binding to GABA receptors and potentiating the activity of GABA** It is worth noting that these drugs bind to a different spot on the GABA receptor from the benzodiazepines and some other anesthetic induction agents
51
T/F: Buprenorphine is used in dogs and cats as an analgesic
**True**
52
What is the major side effect association with **NSAID** use?
**Gastric irritation/ulceration** Normal production of mucus in the stomach depends on PGE2 (produced by COX-1). If mucus production is stopped, then the stomach acid will cause ulceration. *This can be prevented by giving PG analogues or PGE1 with the NSAID*
53
What is the inhalant anesthetic drug of choice in critically ill patients for neurosurgery?
**Isoflurane** It causes less cerebral vasodilation than halothane, maintains cerebral vascular autoregulation, and is anticonvulsant, making it a good choice for patients with neurological issues
54
Which local anesthetic drug that we've discussed in class is considered to be the most **cardiotoxic**?
**Bupivacaine** Bupivacaine is the 2nd most widely used local anesthetic (2nd to lidocaine). Due to its cardiotoxicity, the *maximum dose for Bupivacaine is 2 mg/kg*
55
T/F Edrophonium is a reversible acetylcholinesterase inhibitor used to therapeutically treat Myasthenia Gravis
**False.** Edrophonium is used to **_diagnose_** Myasthenia Gravis
56
Which drug is considered the most important phenothiazine for the purposes of sedation?
**Acepromazine** It is frequently used along with opioids to produce neuroleptanalgesia for chemical restraint or as anesthetic premedication
57
A dual COX and 5-LOX inhibitor used for the treatment of pain and inflammation associated with osteoarthritis in dogs:
**Tepoxalin** Dual COX & 5-LOX inhibitors potentially have a broader anti-inflammatory spectrum than pure COX or 5-LOX inhibitors
58
Which is the primary indication/use for Pentobarbital?
Euthanasia
59
T/F: A partial agonist is a drug that produces a maximal response by occupying a fraction of the receptors.
**False** A partial agonist binds to receptor but does not cause as much effect as a full agonist. However, it still blocks that receptor from full agonist binding
61
T/F: Diazepam may be used as an appetite stimulant in dogs and cats
**True**
61
What would be an appropriate prescription to induce muscle relaxation in a dog with Intervertebral Disk Disease (IVDD)?
**Methocarbamol** Methocarbamol (a muscle relaxant with a central of action at the spinal cord) is used as an adjunct for treating acute inflammation and traumatic conditions of skeletal muscles, and to reduce muscle spasms.
63
Why is morphine not typically given IV?
**histamine release** It causes more histamine release when given IV than the other opioids and for this reason most people do not use it IV.
65
Hyperprolactinemia is an adverse effect of:
**Phenothiazines**
66
**Aspirin** and **Paracetamol **have exceptionally long half-lives in which species?
**Cats**
67
T/F: Inflammation inhibits NSAID distribution to peripheral tissues
**True** Inflammation inhibits NSAID distribution to peripheral tissues, *but then delays clearance from these tissues. *
68
The toxic dose of lidocaine in most species is about \_\_\_\_\_\_\_\_\_
The toxic dose of lidocaine in most species is about **_7 mg/kg_**. SHEEP ARE THE MOST SENSITIVE SPECIES!!!
69
What is the mechanism of action by which Benzodiazepines cause CNS depression?
Bind to and **activate** **GABA** Remember that GABA is the primary inhibitory neurotransmitter in the mammalian CNS, so anything that potentiates its action will decrease neuronal firing by hyperpolarizing the neurons thus making them less responsive to incoming action potentials
71
T/F: Acepromazine provides decent analgesia
**False** Acepromazine does not provide any analgesia
72
**Phenylbutazone** has an unexpectedly long half-life in *which species*?
**Cattle**
73
Which NSAID is considered the most potent for analgesic use in equine colic?
**Flunixin** There have been some cases where the analgesia provided by flunixin was potent enough to hide severe ischemic damage to the gut that should have been treated surgically
75
Which of the following cholinesterase inhibitors may have less systemic adverse effects because of a shorter duration of action? * a. physostigmine * b. neostigmine * c. edrophonium * d. pyridostigmine * e. organophosphate
**edrophonium**
77
Reversal agent for Diazepam?
**Flumazenil**
79
Dogs with *which gene mutation* may show more profound clinical effects and longer duration with Acepromazine?
**MDR1 gene mutation**
80
Which of the following is true regarding **Isoproterenol**? * Commonly used to treat bradycardia * The most potent positive inotrope * Causes uterine contraction * Leads to vasoconstriction * None of these are true
**The most potent positive inotrope**
81
**Naproxen** has a very long half-life in *which species*?
**Dogs** Naproxen has a very long half-life in dogs and has killed several; ibuprofen is much better at producing ulcers in dogs than in people
82
T/F: It is recommended to give 100% oxygen on recovery after using **Nitrous Oxide**
**True** On recovery, the nitrous in the body will diffuse out and occupy the space within the alveolus. *This can displace other gases in the alveolus (most importantly oxygen), leading to hypoxia, thus it is recommended to give 100% oxygen on recovery*. This is referred to as the **Fink Effect (diffusion hypoxia)**
83
T/F: The MOST common phase II metabolic reaction is conjugation to glucuronic acid.
**True**
84
T/F: Nitrous Oxide has a very high MAC (in animals 200-250%) thus it is a very potent inhalant
**False** Nitrous Oxide *does* have a very high MAC (in animals 200-250%), but this means **_it is not a potent inhalant_**
85
T/F: Generally, drugs that bind extensively to plasma protein tend to have short half-lives.
**False**
86
What is the most widely used alpha-1 agonist in dogs suffering from urinary incontinence?
Phenylpropanolamine
87
T/F: For most drugs, the half-life (t1/2) depends on the dose of drug administered
**False**
88
What is the term used to describe a seizure lasting at least 5 minutes or two or more discrete seizures without full recovery of consciousness between seizures?
**Status Epilepticus** THIS IS AN EMERGENCY SITUATION!! Give Diazapam!!!
90
Name an opioid drug mainly used in the symptomatic treatment of diarrhea:
**loperamide**
91
Which breed is particularly sensitive to the cardiovascular effects of phenothiazines?
**Boxers** You can still use phenothiazines on boxers, but you may want to be a little more careful with dosing
92
Which of the following agents can be used to enhance renal excretion of aspirin in cats? * atropine * ammonium chloride * epinephrine * sodium bicarbonate * methionine
**sodium bicarbonate** Using HCO3- to alkalinize the urine will enhance renal excretion of weakly acidic drugs, such as aspirins
93
T/F: Inhalant anesthetics are capable of producing dose-dependent CNS depression, immobility in response to pain, muscle relaxation, and analgesia
**False** These agents produce dose-dependent CNS depression, immobility in response to pain, & muscle relaxation, but **_generally do not provide analgesia_\*\*** \*\*the exception to this rule is Nitrous Oxide
95
T/F: Isoflurane causes significantly less respiratory depression than halothane
**False.** Respiratory depression caused by Isoflurane is very similar to that of halothane. Isoflurane causes less *cardiac depression* than halothane
95
What is the mechanism of action for **Propofol**?
As with barbiturates, **Propofol binds to and potentiates GABA receptors in the CNS**
96
Which species seems to be most prone to the gut side effects of NSAIDs?
**Dogs** This is possibly because NSAIDs undergo enterohepatic recirculation in dogs, but there is rarely (if ever) a dog death from gut ulcerations following NSAID use
97
**Thiopental** induces dose-dependent respiratory depression with transient apnea with initial bolus. Which species is most sensitive to this respiratory depression?
**Cats**
98
Which of the following neoplasias are not likely to respond well to treatment with piroxicam? * Bladder transitional cell carcinoma (TCC) * Mammary adenocarcinoma * Transmissible venereal tumor (TVT) * Subungual malignant melanoma
**Subungual malignant melanoma**
99
T/F: Etomidate is the drug of choice for inducing anesthesia in patients with Addison's Disease (hypoadrenocorticism)
**F.A.L.S.E.** Using Etomidate in Addison's Disease patients is a CONCERN because *Etomidate causes transient suppression of adrenal steroid production*. Note though that this adrenocortical suppression is not really clinically significant in healthy patients
100
Which cyclooxygenase is produced constitutively?
**COX-1** COX-1 is constitutive; produced pretty much all the time at the same rate COX-2 is inducible; expression is dramatically increased in association with inflammation
101
**Diazepam **is used as a muscle relaxant, typically as part of an anesthetic protocol. If prolonged muscle relaxation is needed, which other benzodiazepine may be used?
**alprazolam** Duration of action is much greater than that of diazepam (Alprazolam has also not been associated with hepatic necrosis when given orally to cats, so that's pretty neat)
102
With regard to inhalant anesthetics, the most clinically relevant measure of solubility is:
**the blood/gas coefficient** This is important to us because it is a *direct reflection of the speed of induction and recovery, as well as response to changes in dose of the anesthetic drug*
103
What is the drug of choice to treat ventricular arrhythmias in the dog?
**Lidocaine**
104
Name 2 selective COX-2 inhibitors
**Firocoxib** and **Robenacoxib** \*\*Etodolac may also be selective for COX-2 in horses
105
All of the following are therapeutic uses of phenothiazine derivatives **except**: * anti-motion sickness * antihistamines * preanesthetics * analgesics * antiemetics
Phenothiazine derivatives are not used as **analgesics** Phenothiazine derivatives can be used as preanesthetics (in combo with opioids), antihistamines (trimeprazine), anti-emetics, and anti-motion sickness drugs (chlorpromazine, Prochlorperazine)
106
Reversal agent for **Dexmedetomidine**
**atipamezole** atipamezole is an α2 antagonist used in dogs in cats for reversal of α2 agonist drugs
107
Atipamezole is a: * antimuscarinic * central a2-adrenergic agonist * central a2-adrenergic antagonist
Atipamezole is a **central a2-adrenergic antagonist** It is used clinically to reverse a2 agonist sedative or CV effects, specifically for dexmedetomidine
108
Which opioid do we regard as the **most potent analgesic** used in small animals?
**Fentanyl** ~100x more potent than morphine
110
Which drug would you choose for routine reversal of a dog sedated with **Dexdomitor®** for a minor nonpainful procedure?
**Atipamezole** Dexdomitor® is a brand name for **dexmedetomidine**
111
Which drug can be used to rapidly remove competitive neuromuscular blockers (such as Ruconurium) by chelation?
**Sugammadex** Sugammadex is an agent for reversal of neuromuscular blockade by the agent rocuronium in general anaesthesia.
111
T/F: Diazepam may be used for acute or chronic management of seizures
**False** Diazepam is great for acute management of seizures, however because it has a very short duration of action, it is not good to use for chronic management of seizures.
113
T/F: Lidocaine is known to have a decreased duration of action when given with adrenaline
**False** Lidocaine has an *increased duration of action *when given with adrenaline (~1 hour). Duration without adrenaline is ~30-40 minutes
115
What is the mechanism of action for **alphaxalone**?
Alphaxalone **binds to and potentiates GABA receptors in the CNS**
116
All of the following drugs are clinically used as opioid antagonists **except**: * naloxone * buprenorphine * natrexone * diprenorphine * nalorphine
**buprenorphine** Buprenorphine is an partial opioid *agonist*
118
Which of the following drugs is **preferred** in the treatment of acetaminophen toxicity? * atropine * xylazine * misoprostol * acetylcysteine * succinylcholine
**Acetylcysteine** Acetaminophen produces toxic metabolites, particularly in cats. These toxic metabolites are usually mopped up by glutathione, but liver glutathione reserves can be quickly used up and methemoglobinemia and liver damage may result. Acetylcysteine can be given as a source of glutathione but prevention is better than cure – acetaminophen is best avoided in both cats and dogs
119
Which is an anti-motion sickness and anti-emetic? * Azaperone * Droperidol * Medetomidine * Prochlorperazine
**Prochlorperazine**
120
The emetic effect of **apomorphine**, an opioid drug, is mediated through the stimulation of _____________ receptors in the Chemoreceptor Trigger Zone (CRTZ)
**dopamine (D2-like) receptors**
121
T/F: The more soluble the anesthetic agent (higher blood/gas coefficient), the longer it will take to reach equilibrium
**True** A more soluble drug will want to get in the blood and spend more time in the blood. The blood is acting like a big sponge that is soaking up and 'holding' the anesthetic drug
122
The drug of choice for maintenance therapy of epilepsy in dogs and cats is:
**phenobarbital**
123
T/F: Phenoxybenzamine is the drug of choice for Pheochromocytoma
**True**
124
T/F: **NSAIDs** can produce analgesia in the presence or absence of inflammation
**True** This is a big difference from steroids! Steroids are not directly analgesic (they are potent anti-inflammatories, and by removing inflammation they can reduce pain) *NSAIDs are different in that they can produce analgesia in the absence of inflammation*
126
Name a mixed opioid agonist-antagonist that is used to partially reverse full µ agonists and reduce dysphoria and cardiorespiratory depression *without completely reversing analgesia*
**Butorphanol**
127
COX inhibition is usually assessed by measuring the reduction in circulating \_\_\_\_\_\_\_\_\_\_
**thromboxane B2**
128
Which of the following drugs is favored in the treatment of glaucoma? * pilocarpine * bethanechol * neostigmine * muscarine * carbachol
**pilocarpine** Pilocarpine is a nonselective muscarinic agonist
129
Of dogs and cats, which species is most susceptible to the emetic effects of **a2** **agonist** drugs? Why?
**Cats** a2 agonist drugs activate a2 receptors in the chemoreceptor trigger zone (CRTZ), causing emesis. This effect is more apparent in cats because **cats have more a2 receptors in the CRTZ than dogs do**
130
What is the drug of choice for treatment of anaphylactic shock?
**epinephrine**
132
The reversal agent for benzodiazepines is:
**flumazenil**
133
**Metomidate** is used as an anesthetic in what species?
**fish** Metomidate (Aquacalm®) is a fish anesthetic
134
What is the primary mechanism of action of NSAIDs?
**Inhibition of COX** and thus diminished generation of thromboxane, prostacyclin, and prostaglandins (particularly PGE2)
135
Does **Thiopental** increase or decrease intracranial pressure?
**Thiopental decreases intracranial pressure**
136
What is the most commonly used drug to induce vomiting in canines?
**Apomorphine** Apomorphine is the most commonly used (and probably the most effective) emetic in canines, *typically to treat toxin ingestion*
137
A weak basic drug is expected to: * be readily absorbed from the stomach * have a low volume of distribution (Vd) * be rapidly excreted in urine in cattle * be excreted in milk in large quantities * cross the blood-brain barrier poorly
**A weak basic drug is expected to be excreted in milk in large quantities** Weak basic drugs suffer ion trapping in milk, causing them to be excreted in larger quantities at a time
138
Which of the following generally requires concurrent use of a muscle relaxant? * A. Thiopental * B. Propofol * C. Alfaxalone * D. Ketamine * E. Etomidate
**D. Ketamine**
139
T/F: **Propofol** is inherently arrhythmogenic and sensitizes the heart to epinephrine
**False** Propofol does sensitize the heart to epinephrine, **_but is not inherently arrhythmogenic_**
140
T/F: NSAIDs are much safer than opioids to use with head trauma patients
**True**