VM 584 Pharmacology Final

Which of the following bacteria are likely to have higher MIC levels due to the nature of the bacteria?  

A. Rhodococcus

B. Pseudomonas

C. Streptococcus

D. Pasturella

B.

Name intrinsic defenses of Pseudomonas that make this species so hard to kill

• Restricted outer membrane permeability

• Efflux pumps reduce the drugs intracellular concentration

• Production of beta-lactamases

Biofilm:

A. functions as a protective, single layer structure that allow bacteria to adhere to surfaces and protects them from the environment.

B. functions as a protective, three dimensional structure that allow bacteria to adhere to surfaces and shields bacteria from the environment.

C. functions as a protective, three dimensional structure that prevents bacteria from adhering to surfaces and protects them from the environment.

D. enhances the effects of antimicrobials by increasing bacteria exposure to drugs trapped within the film.

B.

Which of the following are factors which may make treating a prostate infection difficult in an older male dog:  (Select all that apply)

A. Antimicrobials can freely enter the prostate gland just like they can muscle tissue because it is a well vascularized gland.

B. The blood-prostate barrier can limit antimicrobials from entering the prostate gland

C. The difference in pH between plasma and prostate gland/prostatic fluid may influence the concentration and activity of some antimicrobials

D. The prostate gland has a relatively limited blood supply, which may prevent tissue concentrations from reaching therapeutic levelsWhat does it mean if the MIC for a specific pathogen is greater than an antimicrobial break point?  

B. C. D.

What does it mean if the MIC for a specific pathogen is greater than an antimicrobial break point?  

A. The antibiotic is unlikely to achieve therapeutic success at safely attainable doses.

B. At typical doses, the antibiotic has a high probability of being effective.

C. The antimicrobial dose must be doubled to achieve therapeutic levels long enough to be effective.

D. An antibiotic may be effective at higher doses (if safely attainable) at specific infection sites based on the PK/PD of the drug.

A.

T/F: MICs change over time as bacterial populations evolve and change  

True

Which of the following antimicrobials are most likely to have a PAE (Post Antibiotic Effect)?  

A. Penicillins like Cephalosporin

B. Aminoglycosides, like Gentamicin

C. Macrolides like Azithromycin

D. Sulfas, like TMS

E. Penicillins like Amoxicillin/Clavulanic Acid

B. — concentration-dependent abx have greater post-antibiotic effect

What is the simplest method of prolonging the presence of time dependent drugs?  

A. Shorten the dosing interval.

B. Increase the dosing interval

C. Double the dose

D. Do not change anything it does not matter.

A. — can be done via CRI or more frequent intermittent doses

Name 3 steps to antimicrobial selection

1. Establish need to treat

2. Identify bug and drug

3. Design dosing regimen

Name 3 microbial factors that affect antimicrobial efficacy

• Virulence: aggressiveness of bacteria

• Resistance to specific antimicrobials or antimicrobial classes

• Size of inoculum

T/F: Antimicrobial resistance takes time to develop

False

Difference between inherent vs acquired antimicrobial resistance

Inherent - genes present naturally

Acquired - may be naturally acquired or may be driven by antimicrobials and/or disinfectants

Difference between vertical acquired microbial resistance vs horizontal acquired microbial resistance

Vertical - mutation, part of the bacterial genome

Horizontal - shared either by transformation, transduction, or conjugation

Which host factor is most likely to decrease antibiotic effectiveness by acting as a physical barrier AND binding/inactivating the drug?

A. Acidic pH
B. Purulent exudate
C. Decreased oxygen tension
D. Hyperosmolar environment
E. Fibrous tissue formation

B. — purulent exudate acts as a physical barrier, dilutes drugs, binds/inactivates, provides acidic pH, and acts as a hypersmolar environment. Other factors include decreased O2 tension and fibrous tissues.

T/F: Phagocytic white blood cells can enhance the efficacy of some antibiotics by accumulating the drug and delivering it to the site of infection.

True - Up to 100-fold increase compared to plasma, can act with distribution of drug to site of infection 

Which of the following statements about privileged sites and drug penetration is TRUE?

A. The blood–brain barrier allows most hydrophilic antibiotics to penetrate easily.
B. Bone tissue is easily reached by antibiotics due to high blood supply.
C. The cornea blocks drugs depending on their lipophilicity or hydrophilicity.
D. Joints allow for good penetration due to the connective tissue present

C.

Which of the following would you NOT use in aerobic environments?

A. Aminoglycosides

B. Fluoroquinolones

C. Sulfonamides

D. Nitroimidazoles

D.

What is a breakpoint of a drug?

A breakpoint is a specific MIC of a drug that is selected to predict the clinical outcome for a specific pathogen, in a specific disease, in a specific species, and with a specific dosing regimen.

Breakpoints help clinicians determine whether a pathogen is susceptible, intermediate, or resistant to an antimicrobial, guiding effective therapy.

What is the mutant prevention concentration?

The minimum drug concentration that inhibits the growth of the least susceptible single-step mutant in an infection bacterial population

Which of the following mechanisms contribute to fluoroquinolone resistance in bacteria? Select all that apply

A. Chromosomal mutations reducing the affinity of DNA gyrase and topoisomerase IV for the drug
B. Overexpression of endogenous multidrug resistance MDR efflux pumps
C. Production of beta-lactamases

A. and B.

Which of the following statements about MIC and MBC (minimum bactericidal concentraiton) is CORRECT?

A. For bactericidal drugs, the MBC is much higher than the MIC.
B. For bacteriostatic drugs, MIC ≈ MBC.
C. For bactericidal drugs, MIC ≈ MBC.
D. MIC and MBC are always identical for all antibiotics

C. — bactericidal drugs can kill bacteria at concentrations similar to those that inhibit growth → MIC = MBC

bacteriostatic drugs inhibit growth but require much higher concentrations to kill → MBC » MIC

Which of the following statements is correct regarding the administration of beta-lactam antibiotics for gram-negative infections?

A) Beta-lactams are bactericidal and can be given once daily regardless of the pathogen.
B) For gram-negative bacteria, beta-lactams need to be maintained at or above the minimum inhibitory concentration (MIC) for 100% of the dosing interval, often requiring more frequent dosing.
C) Beta-lactams are bacteriostatic and timing of doses is not important.
D) Beta-lactams work best when given as a single high dose rather than multiple smaller doses.

B. — time-depedent bactericidal drugs

Which of the following statements correctly describes concentration-dependent antibiotics?

A) Their efficacy depends on maintaining drug levels above the MIC for the entire dosing interval.
B) They generally require multiple daily doses to maintain effectiveness.
C) High peak concentrations are important, with a Cmax approximately 10–12× MIC, and they often have a significant post-antibiotic effect (PAE).
D) They are mostly effective against gram-positive bacteria and less so against gram-negative bacteria.

C.

Which of the following statements correctly describes time-dependent antibiotics?

A) Their efficacy depends on achieving a high peak concentration, with Cmax 10–12× MIC.
B) They have minimal post-antibiotic effect, and drug levels must remain above the MIC for a significant portion of the dosing interval.
C) Once-daily dosing is generally sufficient regardless of the pathogen.
D) They have irreversible effects on bacteria and efficacy is largely independent of the time above MIC.

B.

Which of the following are time-dependent drugs? Select all that apply

A. Beta-lactams

B. Aminoglycosides

C. Fluroquinolones

D. Phenicols

A. and D.

MOA of azoles

Inhibit lanosterol 14-α-demethylase, blocking ergosterol synthesis and causing toxic sterol accumulation that disrupts fungal cell membrane integrity

What antifungal is particularly effective against aspergillus?

A. Fluconazole

B. Voriconazole

C. Itraconazole

D. Amphotericin B

C.

T/F: Compounded itraconazole has excellent bone penetration

False - Do not use compounded itraconazole but it does have excellent bone penetration

Adverse effects of itraconazole and fluconazole

• GI signs especially in cats

• Hepatoxicity

• Skin issues

What major metabolic system do azole antifungals inhibit, leading to numerous drug interactions?

They are potent CYP450 enzyme inhibitors, which increases the risk of drug interactions

T/F: Ketoconazole appears to have greatest hormonal suppression, with itraconazole having lesser effect 

True

Spectrum of action for voriconazole

• Dimorphic fungi

• Aspergillus/Penicillium spp.

• NOT zygomycetes

T/F: Voriconazole can be used safety in cats

True - but cats more susceptible to adverse effects

Which of the following antifungals are used to treat some aspergillus infections in birds?

A. Fluconazole

B. Voriconazole

C. Itraconazole

D. Amphotericin B

B.

T/F: Horses taking voriconazole can be susceptible to adverse effects including hepatotoxicity and neurotoxicity

False - pruritis reported in horses - used for systemic treatment of equine keratomycosis

How long should you treat ear fungal infections?

3 weeks

MOA of amphotericin B

Alters ergosterol cell membrane

What is a key advantage of encochleated amphotericin B in terms of immune cell interaction?

It has enhanced macrophage uptake, improving delivery to infected tissues.

Adverse effects of Amphotericin B

Nephrotoxicity — give as slow drip with saline diuresis

Which of the following statements is FALSE regarding antifungal agents?

A. Terbinafine is fungicidal for dermatophytes, concentrates in the stratum corneum, and is often used as a single agent for superficial mycoses.
B. Griseofulvin is fungistatic, interferes with mitotic spindle formation, and is active against both dermatophytes and Candida species.
C. Flucytosine requires fungal conversion to 5-FU via cytosine deaminase and is synergistic with amphotericin B against Cryptococcus and Candida.
D. Dietary fat enhances absorption of griseofulvin, and dosing differs between microsize and ultramicrosize formulations.

B.

What is key when utilizing topical antifungal shampoos for bathing a dog or a cat with a Malassezia skin infection?  

A. The bath water must be extremely hot to activate the shampoo.

B. The time of contact of the shampoo on the skin.

C. The bath water must be cool to activate the shampoo.

D. The shampoo must be repeated twice per day with an 8 hour rest period between baths.

B.

Which of the following antimicrobials is most efficacious for treating anaerobic infections?  

A. Metronidazole

B. Aminocyclitol type drugs including the aminoglycosides gentamicin and amikacin

C. Sulfonamide drugs like Trimethoprim-sulfamethoxazole.

D. Fluoroquinolone antimicrobials like enrofloxacin

A.

Which of the following complete this sentence:  "A breakpoint is a specific MIC of a drug selected to predict the clinical outcome for a:"  Select all that apply

A. in specific patient species

B. May only be described as Susceptible (S), intermediate susceptibility (I), Facultatively susceptible (F), and Resistant (R).

C. specific pathogen

D. given a specific drug regimen (Dose, route, duration of therapy, frequency of drug administration)

E. in a specific disease

A. C. D. E.

T/F: Post antibiotic effects (PAE) are more likely to happen in concentration vs time dependent drugs.  

True

Which of the following drugs has been shown to have the greatest adverse effects on the reproductive system?  

A. Terbinafine

B. Cefpodozime

C. Ketoconazole

D. Penicillin

E. Cephalexin

C.

What is often, or should be administered,  in conjunction with Griseofulvin?  

A. A high carbohydrate meal to enhance dietary absorption

B. A high fat meal to enhance dietary absorption.

C. Microsized griseofulvin is effectively absorbed from the GI tract.

D. A low fat meal to enhance dietary absorption

E. A high protein meal to enhance dietary absorption

B.

Most molds, including Aspergillus spp are intrinsically resistant to which of the following antifungal drugs?  

A. Fluconazole

B. Amphotericin B

C. Itraconazole

D. Posaconazole

E. Voriconazole

A.

Azole efficacy is best predicted by:

A. using AUC > 125 times MIC to determine desired plasma concentrations.

B. by plasma concentrations equal to MIC.

C. plasma concentrations of 10-12 times MIC

D. using an AUC/MIC ratio >25 to determine desired plasma concentrations.

E. by plasma concentrations above MIC 75% of the time.

D.

Mycophenylate mofetil is what type of drug?

A. A precurser drug which is synthesized to the inactive form, mycophenolic acid by the liver
B. A prodrug which is metabolized to the active form, mycophenolic acid by the liver
C. A prodrug which is synthesized to the active form, mycophenolic acid by the stomach
D. Is the active form as administered, so it requires no additional metabolism to have an effect.

B.

What is the mechanism of action of Cyclosporine?

A. Blocks activation of T cells by inhibition of IL2 transcription
B. Stimulates the immune system to prevent infection
C. Stimulates the appetite of anorexic cats
D. Blocks activation of B cells by inhibition of IL1 transcription

A. — calcineurin inhibitor,

T/F: Cyclosporine can inhibit cytokine production and release affecting the function of eosinophils, mast cells, granulocytes and macrophages

True

What is a recommended first line therapy for IMHA based upon the ACVIM Consensus Statement?

A. Depomedrol may be administered IM on a temporary basis if the patient initially will not tolerate PO drugs.
B. Dexamethasone may be administered IV on a temporary basis if the patient initially will not tolerate PO drug therapy.
C. Prednisolone may be administered IV on a temporary basis if the patient initially will not tolerate PO drug.
D. Depoprovera may be administered IV on a temporary basis if the patient initially will not tolerate PO drug.

B.

Which of the following drugs are considered viable 2nd drug options for the treatment of IMHA in dogs (Pick all answers that apply)

A. Azathioprine
B. Mycophenolate
C. Sulfasalazine
D. Cyclosporine

A. B. D.

Per the ACVIM consensus statement on treating IMHA in dogs, what is a key recommendation for therapy if 3 or more drugs are used to manage refractory patients?

A. Include concurrent administration of azathioprine and mycophenolate mofetil.
B. Use drugs that target different immune pathways
C. Use drugs that target the same immune pathways
D. A long acting drug like sulfasalazine must be included

B.

Concurrent administration of what two drugs used to treat IMHA is not recommended because both are immunosuppressants that inhibit purine synthesis?

Azathioprine and Mycophenolate mofetil

Therapeutic drug monitoring should be considered for which of the following drugs used to treat IMHA?

A. Cyclosporine
B. Prednisolone
C. Doxycycline
D. Omeprazole
E. Pantoprazole

A.

Which of the following are considered to be an adverse effect/side effect of glucocorticoid therapy in dogs receiving oral corticosteroids to treat IMHA? select all that apply.

A. Soft formed feces
B. Lethargy and weakness
C. Excessive panting
D. Polyphagia
E. Polyuria and polydypsia

B. C. D. E.

What is a preferred platelet inhibitor alternative to low dose aspirin to prevent thromboembolism in dogs with IMHA that can be administered orally?

A. Antiplatelet drugs are not indicated for IMHA.
B. Clopidogrel
C. Flunixin meglumine
D. Low molecular weight heparin

B.

Difference between extravascular vs intravascular hemolysis

• Extravascular: outside of blood vessels, mainly spleen and liver macrophages, Fc-mediated phagocytosis of antibody-coated RBCs → more mild anemia, spherocytes, can be icterus

• Intravascular: inside blood vessels, complement MAC formation, RBCs lyse directly in circulation → severe anemia, ghost cells, hemoglobinemia, hemoglobinuria

Name the 3 events that lead to thrombosis

• Endothelial injury

• Altered blood flow

• Hypercoagulabitlity

Arterial clots are mostly composed of ___________ while venous clots are mostly _________

platelets - red clots

fibrin - white clots

Which of the following is the LEAST helpful in aiding with the diagnosis of IMHA?

A. PCV < 20

B. Evidence of hemolysis

C. Ruled-out other causes for anemia

D. Flow cytometry

E. Coombs Test

E. — can be negative with IMHA

Cornerstone of treatment for IMHA

Suppress production of anti-RBC antibody production with immunosuppressive medication (steroids to start)

When would a blood transfusion be warranted in a patient with IMHA?

• Clinical signs → weakness, tachycardia, tachypnea

• Rapid decrease in HCT

• Acute presentation

MOA of a immunosuppresive dose of steroids

• Macrophages: shift from inflammatory → anti-inflammatory phenotype.

• Dendritic cells: decreased antigen presentation.

• T cells: interference with co-stimulatory signals needed for activation and differentiation.

• Overall: suppression of both innate and adaptive immunity.

MOA of Mycophenylate mofetil

Immunosuppressant agent → inhibits de novo synthesis of purines → deprivation of proliferating T and B cells of nucleic acids

MOA of azathioprine

Immunosuppressant agent → purine analog → inhibits purine synthesis

MOA of Clopidogrel

Platelet inhibitor → irreversible ADP inhibitor → prevents platelet activation and aggregation

What is the role of aspirin in IMHA treatment?

Platelet inhibitor → irreversible inhibits thromboxane necessary for platelet activation

A dog is receiving unfractionated heparin CRI for thromboprophylaxis. Which of the following statements is TRUE regarding its use?

A. It works by irreversibly blocking platelet ADP receptors

B. Anti-Xa activity is routinely monitored in all patients
C. It dramatically increases antithrombin III activity, inhibiting thrombin and Factor Xa

D. Hemorrhage is an extremely rare side effect

C. →

A. is Clopidegel

B. Best way to monitor effectiveness but not usually done, measure APTT instead

T/F: Using low molecular weight heparin as an anticoagulant treatment for IMHA has a low risk of hemorrhage

True → Small fragment prevents bridging of AT and thrombin and so cannot inactivate thrombin → Inactivate Fxa 

Which of the following are considered a fundamental principle of pain management in small animals?

A. Pain management protocols should be the same for all animals of the same species.
B. Animals do not feel pain because pain is a sensation unique to humans only.
C. Pain is generally the worst immediately after injury and will become less within 10 to 12 hours even if there is a need for surgery.
D. Pain may change over time, requiring individual tailored pain management plans and a multimodal approach to pain management

D.

What is the general mechanism of action of Non-steroidal Anti-inflammatory (NSAID) drugs?

A. NSAIDS inhibit cyclooxygenase isoenzymes in the Arachidonic Acid pathway.
B. NSAIDS work in the Arachidonic Acid Pathway by stimulating peroxidase enzymes
C. NSAIDs work in the Arachidonic Acid Pathway by inhibiting the release Arachidonic acid from phospholipid membranes.
D. NSAIDS stimulate cyclooxygenase isoenzymes in the Arachidonic Acid pathway.

A.

T/F: There have been reports of idiosyncratic hepatopathy in dogs receiving Carprofen (Rimadyl) with Labrador retrievers being a breed cited.

True

T/F: When administered at labeled doses, Deracoxib (Deramaxx) inhibits COX-2, however as doses are increased there can be significant inhibition of COX-1 which can cause severe adverse GI effects.

True

What is a concern of codeine as pain management drug for dogs?

A. Codeine has a profoundly long half-life making every other day dosing desirable.
B. Codeine has a very short half life, making oral dosing every 2 to 3 hours a necessity
C. Codeine has a very low bioavailability
D. Codeine has no limitations, it is a drug of choice

C.

Tramadol is considered to have some efficacy for pain management in which small animal species?

A. Horses
B. Cattle
C. Cats
D. Dogs

C.

What is the mechanism of action of Librella (bedinvetmab)?

A. Bedinvetmab is a canine (IgM) polyclonal antibody (pAb) that binds to nerve growth factor (NGF), subsequently inhibiting the binding of NGF to its receptors and inhibiting the release of pain mediators
B. Bedinvetmab is a g-protein couple agonist that triggers the release of a small molecule called GDP from it's associated G protein which sets off a cascade of signals that activate the body's pain-relief pathways.
C. Bedinvetmab is a canine (IgG) monoclonal antibody (mAb) that binds to nerve growth factor (NGF), subsequently inhibiting the binding of NGF to its receptors and inhibiting the release of pain mediators
D. Bedinvetmab works by inhibiting the COX-1 and COX-2 enzymes of the arachadonic acid pathway, thus preventing the release of inflammatory mediators

C.

Which of the following pharmacologic interventions will lower potassium levels?

A. Terbutaline
B. Calcium Gluconate
C. Buprenorphine
D. Dexmedetomidine

A.

Goals of OA pain management

• Palliate pain

• Weight loss

• Low impact activities

• Mobility diets

Carprofen has greater sensitivity for

A. COX-1

B. COX-2

B

Meloxicam should be given to dogs

A. 6 weeks and older

B. 12 weeks and older

C. 6 months and older

D. 12 months and older

C

Which of the following NSAIDs inhibits PGE1 and has a higher risk of GI perforation?

A. Carprofen

B. Meloxicam

C. Deracoxib

D. Firocoxib

C.

Which of the following NSAID is more COX-1 sparing than others and is approved in dogs > 7 months?

A. Carprofen

B. Meloxicam

C. Deracoxib

D. Firocoxib

D.

Which of the following NSAID has only approved for cats who are older than 4 months and greater than 5.5 lbs?

A. Carprofen

B. Meloxicam

C. Robenacoxib

D. Firocoxib

C. — onsior

Why is Grapiprant/Galliprant potentially better tolerated in OA patients for long-term use?

• Highly selective EP4 receptor antagonist, it blocks only the EP4 prostaglandin receptor—the main mediator of pain and inflammation in osteoarthritis—without inhibiting COX-1 or COX-2

• No reduction in protaglandins = no documented kidney or liver toxicity and lower risk of GI effects

T/F: Amantadine, a NMDA receptor antagonist, can be an effective stand-alone treatment in the management of OA

False - NMDA receptor antagonist yes but not effective as stand-alone treatment

Which route of administration for Buprenorphine is preferred for acute pain management in cats? Select all that apply

A. SQ

B. Buccal

C. IM

D. IV

C. D.

Side effects of buprenorphine in cats include all of the following EXCEPT:

A. Elevated temperature
B. Euphoria/dysphoria
C. Mydriasis
D. Tachypnea

D.

How long should you prescribe an NSAID for a post-op orthopedic surgery patient?

14-21d but can be longer if needed

Which type of bacteria organisms are the most common cause of sepsis in neonatal foals?

Gram-negative

Which of the following bacteria is the most common cause of sepsis in neonatal foals?

A. Actinobacillus equuli

B. E. coli

C. Staphylococcus

D. Enterococcus

B.

Which of the following correctly describes the effect of calcium gluconate in a cat with a urethral obstruction?

A. Increases cardiac threshold potential
B. Increases calcium excretion in the distal tubule
C. Decreases potassium absorption in the ileum
D. Increases myocyte update of calcium

A.

Which of the following correctly describes the goal of fluid therapy in cats with urethral obstruction

A. Address hypovolemia
B. Replace pre-renal deficits
C. Restore GFR and provide maintenance fluids for the anorexic patient
D. Address ongoing losses
E. All of the answers are correct

E.

The ideal fluid for resuscitation should be what type of solution?

A. Potassium free
B. Hypotonic
C. Hypertonic
D. Isotonic

D.

Which of the following is a common and anticipated adverse effect of sedation with propofol?

A. Hypertension
B. Apnea
C. Tachycardia
D. Agitation

B.

A small animal patient with acute kidney injury requires reassessment of their fluid therapy plan to monitor for:

A. Response to treatment
B. Evidence of euhydration
C. Evidence of overhydration
D. All of these answers are correct

D.

Which of the following is a correct first line empiric therapy antimicrobial to treat leptospirosis in dogs

A. Doxycycline
B. Enrofloxacin
C. Ampicillin
D. Metronidazole
E. Clindamycin

C.

T/F: In small animal patients' with kidney disease antacid therapy should be considered if gastrointestinal ulceration is suspected or confirmed.

True → PPI recommended

The goals of the fluid therapy in the acute kidney injury patient include:

A. Flushing uremic toxins from the kidneys to reduce levels and prevent ongoing injury
B. Diluting elevated levels of potassium, urea, and creatinine
C. Correction of deficits, providing maintenance fluids, and addressing ongoing losses
D. Forcing diuresis to remove all uremic toxins

C.