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Clinical Pharmacology Exam 3 > Antiparasitic drugs > Flashcards

Antiparasitic drugs Flashcards

1
Q

Pyrimethamine mechanism of action

A
  • Pyrimethamine inhibits dihydrofolate reductase

- Ultimately interferes with folic acid synthesis, which is necessary for DNA and RNA synthesis

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2
Q

Formation of tetrahydrofolic acid

A
  • Look on slide for the pathway
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3
Q

Spectrum of activity for pyrimethamine

A
  • Toxoplasmosis in dogs and cats
  • Neospora in dogs
  • Sarcocystis (EPM) in horses
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4
Q

Toxicity of pyrimethamine

A
  • Fairly safe
  • Don’t need to be concerned as much with adverse effects
  • Possibly bone marrow suppression
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5
Q

Pyrimethamine monitoring

A
  • Recommend a CBC prior to treatment and one or two during the 6 months of treatment
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6
Q

Pyrimethamine length of time and use

A
  • Combination with sulfadiazine for 30-180 days once a day
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7
Q

Amprolium mechanism of action

A
  • Structural analog of thiamine, competing for thiamine uptake into protozoal organisms
  • Parasites take up the amprolium instead of thiamine
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8
Q

Amprolium spectrum***

A
  • Effects are greatest against the first-generation schizont stage, so its use is primarily as a preventative rather than therapeutic medication
  • Only inhibits sexual stages
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9
Q

Amprolium usage

A
  • Used in drinking water of poultry and cattle for prevention and treatment of coccidia
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10
Q

Toxicity of amprolium

A
  • Polioencephalomalacia
  • Polyneuritis
  • Very uncommon
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11
Q

Polioencephalomalacia signs and species

A
  • get from slide
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12
Q

Polyneuritis signs and species

A
  • get from slide
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13
Q

Amprolium labeled use***

A
  • Labeled for food animals

- ELDU in dogs, cats, and others

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14
Q

Clindamycin mechanism of action

A
  • Long-term exposure to low concentrations of clindamycin reduces the level of replication of T. gondii
  • Affects the protein synthesis of free parasites
  • Impairs the ability of tachyzoites to infect host cells
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15
Q

Clindamycin spectrum of activity***

A
  • AGENT OF CHOICE for treatment of toxoplasmosis
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16
Q

Route of clindamycin

A
  • PO or IM (can be a disadvantage)
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17
Q

Length of treatment for clindamycin

A
  • 3-6 weeks
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18
Q

Toxicity for clindamycin

A
  • CAUTION is advised when treating cats with pulmonary toxoplasmosis because of several unexplained feline deaths in experimental drug trial
  • have client sign a consent form
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19
Q

Clindamycin for anaerobic infection changes

A
  • Oral or IM at higher doses than for anaerobic infections for 2-4 weeks
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20
Q

Mechanism of Metronidazole

A
  • Intermediate metabolites affect DNA
  • Alter essential metabolic pathways critical for protozoa survival
  • Anti-protozoal action effect related to this mechanism
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21
Q

Spectrum of activity for Metronidazole**

A
  • Often the first-line agent of treating giardiasis

- It is effective against trichomonas in cattle, but CANNOT be used in cattle

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22
Q

Toxicity of Metronidazole**

A
  • Dose-dependent vestibular toxicity (generally slowly reversible)**
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23
Q

Metronidazole species use***

A
  • While its use is considered extra-label in all veterinary species, its use in food-producing animals is prohibited
  • Interesting that it’s prohibited in food animals but used in humans
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24
Q

Triazines

A
  • Ponazuril (Marquis)

- Diclazuril (protazil)

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25
Q

Mechanism of triazines

A
  • Believed to act on the apicoplast of protozoal organisms; but, downstream effects are not clearly defined
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26
Q

Triazines spectrum of activity**

A
  • Class of drug has been used as a coccidiostat in poultry
  • Most recent use as FDA-approved treatment and prevention for Sarcocystis neurona in horses orally for 30 days
  • This is the only option approved by FDA for treatment and prevention
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27
Q

Triazines toxicity***

A
  • Reported toxicities in horses include blisters on nose and mouth, rash/hives, colic, and diarrhea***
  • Any drug given orally can cause adverse effects
    When you incorporate a treatment it can change the microbiota and lead to adverse effects
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28
Q

Ponazuril vs Diclazuril relative adverse effects

A
  • Ponazuril > diclazuril so far, but it has been on the market longer as well
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29
Q

Nitrothiazole example

A
  • Nitrazoxanide = navigator
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30
Q

Nitrothiazole Mechanism of action***

A
  • According to package insert, the compound undergoes reduction to free radicals inside the organism***
  • These free radicals are then thought to interfere with cellular respiration of the target organism***
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31
Q

Spectrum of Nitrothiazole***

A
  • More recent use as an FDA-approved treatment for Sarcocystis neurona in horses, and thought to be more effective than a pyrimethamine-sulfonamide combination
  • Not approved for prevention***
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32
Q

Toxicity of Nitrothiazole

A
  • Severe and potentially fatal enterocolitis
  • Needs a consent form
  • <5% occurrence
  • because Nitrothiazole kills other intestinal parasites (bacterial, protozoal, and helminth), its use can interfere with normal intestinal flora - resulting in severe and potentially fatal enterocolitis
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33
Q

Sulfonamides used in US for treating protozoa

A
  • Sulfadimetoxine
  • Sulfadimetoxine with ormetoprim
  • Sulfadiazine with trimethoprim
  • Sulfametoxazole with trimethoprim
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34
Q

Sulfonamide agent spectrum

A
  • SEE THE TABLE IN THE NOTES

- You must memorize this

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35
Q

Sulfonamide spectrum

A
  • Coccidia
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36
Q

Sulfonamides + pyrimethamine

A
  • Neospora
  • Toxoplasma
  • Sarcocystis
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37
Q

Amprolium spectrum

A
  • Coccidia
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38
Q

Clindamycin spectrum

A
  • Neospora

- Toxoplasma

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39
Q

Metronidazole spectrum

A
  • Giardia

- Trichomona (Ronidazole in cats)

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40
Q

Fenbendazole/albendazole spectrum

A
  • Giardia
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41
Q

Ponazuril/diclazuril spectrum

A
  • Neospora (cattle)

- Sarcocystis

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42
Q

Nitrazoanide spectrum

A
  • Sarcocystis
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43
Q

Anthelmintic resistance most affected species

A
  • horses, sheep and goats

- Resistance to multiple classes of agents has been documented in cattle in New Zealand and South America

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44
Q

What are the three mechanisms of resistance to anthelmintics?***

A
  1. Failure to reach the site of action
  2. Altered target
  3. Inactivation of anthelmintic agent
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45
Q

Which anthelmintics have documented resistance?***

A
  • All major families of broad-spectrum anthelmintics
  • Benzimidazoles and macrocyclic lactones are the two main groups related with resistance (mostly because they are the most used)
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46
Q

What methods are being used to optimize the efficacy of available anthelmintics?**

A
  1. Combining or rotating drugs with different mechanisms of action
  2. Using as few treatments as possible (decrease exposure of parasites to anthelmintics)
  3. Use appropriate doses
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47
Q

How to use appropriate dose in a large animal?

A
  • Try not to estimate the weight
  • In practice he recommends since they are generally quite safe
  • He recommends that we overestimate the dose
  • Except for the drugs with a very narrow therapeutic window
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48
Q

Benzimidazole mechanism of action**

A
  • Strongly binds to parasite free beta-tubulin molecules, affecting the tubulin polymerization and interfering microtubule-dependent processes including cell division, motility and transport
  • May also inhibit enzymatic activity (fumarate reductase primarily**, succinate dehydrogenase, others) resulting in decreased energy production in parasites
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49
Q

Spectrum of activity of benzimidazoles***

A

Broad spectrum!

  • Broadly: GI nematodes, protozoa (giardiasis), fungi, and mites
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50
Q

More info about benzimidazoles spectrum

A
  • Look at the slides
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51
Q

Therapeutic margin of benzimidazoles***

A
  • WIDE THERAPEUTIC margin
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52
Q

***Which drug in the benzimidazoles is most likely to cause toxicity?

A
  • Albendazole
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53
Q

Toxicity of Albendazole in cats***

A
  • Weight loss, neutropenia, mental dullness
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54
Q

Toxicity of Albendazole in dogs***

A
  • Lethargy anorexia
  • Bone marrow suppression
  • Liver toxicity in dogs, mostly seen with prolonged or high-dose therapy (unknown mechanism)
  • Might not use in combination with another drug that reduces bone marrow suppression**
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55
Q

Reproductive effects of albendazole***

A
  • Teratogenic effects may be possible, therefore should not be used in pregnant animals
  • Package insert of albendazole states that it is NOT TO BE USED IN FEMALE CATTLE DURING THE FIRST 45 DAYS OF PREGNANCY***
  • Only described in cattle but probably don’t use in any pregnant animals
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56
Q

Clinical use of benzimidazoles

A
  • At least 10 benzimidazoles marked for use in veterinary species
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57
Q

Fenbendazole efficacy***

A
  • one of the broader spectrum agents with efficacy against: 1.) cestodes, intestinal nematodes (adults and 4th stage larvea); lungworms (adult and larval stages) in cattle, sheep, and goats
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58
Q

Methods of heard dosing for benzimidazoles and formulations**

A
  • Incorporation of drug into water or feed blocks - no direct control
  • Drenching/tubing but time consuming and expensive
  • Ruminal devices - once delivered to the rumen, to coincide with prepatent period of major nematodes of cattle (up to 4 months)
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59
Q

Clinical use of benzimidazoles in SA

A
  • Hookworms
  • Whipworms
  • Tapeworms
  • Taenia but not Echinococcus
  • Giardia
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60
Q

Clinical use of benzimidazoles in horses

A
  • Large and small strongyles
  • Pinworms
  • At higher doses ascarids
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61
Q

Thiabenazole family and use

A
  • Benzimidazole

- Not useful against cestodes and trematodes

62
Q

Febantel family and use

A
  • Pro-drug of fenbendazole
63
Q

Other benzimidazoles

A
  • Look on the slides
64
Q

Withdrawal times for benzimidazoles

A
  • Highly variable depending on species, formulation, and drug
  • Don’t need to memorize specific times
  • see slide
65
Q

Imidazothiazole mechanism of action (levamisole)***

A
  • Agonist at nicotinic acetylcholine receptors on nematode muscle cells (depolarization) resulting in spastic paralysis***
  • Another mechanism described about interference with metabolism of the parasite but is not the primary mechanism of action of this drug
66
Q

Spectrum of levamisole**

A
  • Effective against a variety of GIT and lung nematodes but not cestodes or trematodes
67
Q

Toxic side effects of levamisole

A
  • In mammals, mostly has to do with cholinergic activity of both muscarinic and nicotinic effects
  • SLUD, respiratory distress, bradycardia, asphyxia, CNS depression
68
Q

Antidote of levamisole***

A
  • None

- Cannot give atropine

69
Q

Therapeutic index of levamisole*****

A
  • It is the most toxic anthelmintic

- Therapeutic margin is fairly narrow - depending on species, the margin may be as low as 3x the therapeutic dose

70
Q

What species is most sensitive to levamisole?**

A
  • Sheep appear more sensitive than cattle, while chickens tend to tolerate levamisole quite well
71
Q

Formulations of levamisole/imidazothiazoles

A
  • Tablet, oral solution, oral drench, feed additive, SC injection or topical
72
Q

Methods of herd dosing of levamisole/imidazothiazoles

A
  • Injectable (SQ or IM) or pour on formulations are used in cattle
73
Q

Tetrahydropyrimidines (pyrantel, morantel) MOA***

A
  • Agonist at nicotinic acetylcholine receptors on nematode muscle cells resulting in spastic paralysis (similar to levamisole)
  • Secondary mechanism related with acetylcholinesterase but less important
74
Q

Spectrum of Tetrahydropyrimidines (pyrantel, morantel)***

A
  • In horses, GI nematodes
  • At high doses can be used against the ileocecal tapeworm of horses (Anoplocephala perfoliata)
  • In cattle, dogs, and cats, GI nematodes
75
Q

Tetrahydropyrimidines (pyrantel, morantel) toxicity***

A
  • High margin of safety
  • Doses 7x greater than the therapeutic dose produce no signs of toxicity in all major veterinary species
  • Better choice than levamisole for this reason
76
Q

Drug interactions with Tetrahydropyrimidines (pyrantel, morantel)*

A
  • Not recommended to use with other cholinergic agonists (levamisole, others)
  • Don’t use with cholinergic antagonists (piperazine, others) - these cause a flaccid paralysis instead of a spastic paralysis
77
Q

What are the two formulations of pyrantel?

A
  • Pyrantel tartate

- Pyrantel pamoate

78
Q

Pyrantel tartate formulation

A
  • Horses formulated for continuous daily administration for prolonged periods of parasite exposure
79
Q

Pyrantel pamoate formulation in horses

A
  • Horses: administered as suspension or paste as well as mixing with feed
80
Q

Pyrantel pamoate formulation in dogs

A
  • suspension and tablet forms; combined in a tablet with febantel and praziquantel
  • Combined in a chewable containing ivermectin (will affect nematodes, cestodes, and trematodes)
81
Q

Which tetrahydropyrimidine is available for cattle?

A
  • Morantel tartrate

- Cattle-sustained release bolus for both beef and dairy cattle

82
Q

Heterocyclic compounds (piperazine) MOA

A
  • GABA agonist - induces flaccid paralysis in susceptible nematodes
  • Hyperpolarization due to influx of chloride
83
Q

Spectrum of activity of Heterocyclic compounds (piperazine)

A
  • Primarily ascarids

- VERY NARROW SPECTRUM

84
Q

Margin of safety of Heterocyclic compounds (piperazine)

A
  • Wide margin of safety

- Available over the counter

85
Q

Heterocyclic compounds (piperazine) toxic effects

A
  • Wide margin of safety

- Signs of toxicity involve CNS depression (ataxia, weakness, muscle tremors)

86
Q

Piperazine indication

A
  • Dogs, cats, horses for control of ascarids
87
Q

Diethylcarbamazine indication ***

A
  • First heartworm preventive that had to be administered daily (disadvantage)
  • Current use is limited to dogs that don’t tolerate monthly preventatives
  • It’s a heterocyclic compound
88
Q

Melarsomine (arsenical) mechanism of action

A
  • presumed to affect glycolysis
89
Q

Spectrum of activity of Melarsomine (arsenical)

A
  • Adult and 4-month-old heartworms ***
90
Q

Efficacy of single regimen of 2 injections one month apart of Melarsomine (arsenical)

A

> 90%

91
Q

Efficacy of second regimen 4 months later of Melarsomine (arsenical)

A

98%

92
Q

Margin of safety of Melarsomine (arsenical)**

A
  • Very low margin of safety
93
Q

Toxicity of Melarsomine (arsenical)**

A
  • Liver toxicity
  • Nephrotoxicity
  • Aldulticide-induced thromboembolic pneumonia (if heavy parasite load)
94
Q

Adverse reactions specific with melarsomine***

A
  • Injection site reactions
  • Coughing/gagging
  • Depression/lethargy
  • Anorexia/inappetence
  • Pyrexia (fever)
95
Q

About how long can it take for some of the adverse effects with melarsomine to occur?

A
  • Can take about a week for some of them
96
Q

What drug can you use to treat adverse effects of melarsomine?**

A
  • Dimercaprol

- Can be used as a possible antidote

97
Q

When should you administer dimercaprol for it to be effective?***

A
  • Only within the first 3 hours of melarsomine administration (but reduces the effective of melarsomine)
98
Q

MOA of Dimercaprol***

A
  • Binds melarsomine and prevents absorption
  • This is why it has the window
  • May or may not be effective, but it’s the only option
99
Q

***Contraindication of melarsomine

A
  • Contraindicated in dogs with Class 4 (very severe) heartworm disease
  • NOT indicated for cats
100
Q

Melarsomine route***

A
  • A lot of recommendations about where and how to administer
  • The drug must be administered ONLY in the lumbar area in the muscles
  • DO NOT use in any other muscle group. DO NOT USE IV
  • Care should be taken to avoid superficial injection or leakage
  • You must be careful - should not be any subcutaneous leak of the injection –> can lead to abscesses
  • change the side between injections
101
Q

Melarsomine monitoring

A
  • Should be monitored during treatment and for up to 24 hours after the last injection
  • at least 8 hours
102
Q

Goal of melarsomine

A
  • Elimination of ALL adult heartworms with minimal post treatment complications
103
Q

Emodepside mechanism of action***

A
  • Binds to a GPCR (latrophilin like receptor) and via secondary messenger systems releases an inhibitory neuropeptide (possibly GABA) that causes a flaccid paralysis
104
Q

Spectrum of activity for emodepside

A
  • Broad nematodal activity** against both larval and adult forms (including those that havae developed resistance to other antinematodal drugs)
  • Has activity against tapeworms (Dipylidium caninum, Taenia taeniaformis, Ancylostoma tubaeforme)
105
Q

Margin of safety of emodepside

A
  • High margin of safety
106
Q

Emodepside pecies

A
  • Cats and dogs
107
Q

Cat formulation of emodepside***

A
  • Currently approved only for cats as a spot-on formulation (Profender)
  • Contraindicated in kittens under 2 months of age
108
Q

Dog formulation of emodepside

A
  • Have an oral formulation that is tolerated very well
  • In IVERMECTIN-sensitive collies the therapeutic margin of emodepside is significantly lower. Treatment at 2x the therapeutic dose can cause symptoms such as discomfort and uncertain gait
  • Might have to be due with p-glycoprotein export so it concentrates in the brain
109
Q

Important cestodes

A
  • Anoplocephala perfoliata (causes erosions around the ileocecal valve predisposing to intussusception)
  • Dogs (Echinococcus)
110
Q

Choices for anticestodes**

A
  • Pyrantel
  • Morantel
  • Praziquantel
  • Epsiprantel
111
Q

MOA for praziquantel and epsiprantel***

A
  1. Damage integument of the parasites which generates gaps and allows molecules to enter and exist
  2. Causes muscular contraction and paralysis by interfering with calcium homeostasis
    - May not kill them right away but eliminates in the feces
112
Q

Praziquantel spectrum***

A
  • Adult stages of all species of tapeworms of farm and companion animals
  • Has shown 100% activity against E. granulosus in dogs and is considered the treatment of choice*****
  • Some activity against trematodes
113
Q

Epsiprantel spectrum of activity

A
  • Labeled for treatment of common tapeworms in dogs and cats
114
Q

Praziquantel toxicity

A
  • In general quite safe
  • GI toxicity can occur with high doses
  • Has been used safely in pregnant animals
115
Q

Epsiprantel toxicity

A
  • In general quite safe
  • Might be even safer than praziquantel
  • GI toxicity (vomiting) can occur with large overdoses (40x in cats); no signs of toxicity with 36x dose in dogs
116
Q

Antitrematode drugs

A
  1. Clorsulon
  2. Triclabendazole
  3. Praziquantel
117
Q

Main drugs for treating Fasciola

A
  1. Clorsulon

2. Triclabendazole

118
Q

Clorsulon MOA***

A
  • Competitively disrupts glycolysis after its ingestion by the fluke
  • Disrupts synthesis of glucose
  • Affects metabolism of glucose
119
Q

***Spectrum of Clorsulon

A
  • Adult*** liver flukes in cattle, sheep, and goat; some other flukes
120
Q

Margin of safety of clorsulon

A
  • WIDE MARGIN of safety
121
Q

Mechanism of action of Triclabendazole

A
  • Prevents polymerization of beta-tubulin
  • Parasite has problems moving and taking in nutrients
  • May involve binding to tubulin, but at different site than other benzimidazoles
122
Q

Triclabendazole spectrum**

A
  • Adult liver flukes AND immatures to 1-week-old flukes
  • Clorsulon only against adults
  • Significant because it is effective against migratory stages of the parasite that cause tissue damage**
  • Also has greatest antitrematodal activity of all benzimidazoles****
  • This is the best one you can choose
  • In dogs, fenbendazole may be the best choice
123
Q

Albendazole spectrum

A
  • Active against liver flukes older than 12 weeks
124
Q

Safety of triclabendazole

A
  • Wide margin of safety

- In general benzimidazoles are contraindicated against pregnant cattle; same contraindication for triclabendazole

125
Q

Triclabendazole route

A
  • Orally
126
Q

Triclabendazole species***

A
  • Cattle, sheep, and goats
  • Keep withdrawal times in mind (about 2 months)
  • For macrocyclic lactones, they require a longer withdrawal time
127
Q

Clinical use of triclabendazole***

A
  • For treatment of liver flukes - both acute and chronic because it is effective against mature and immature stages (advantage over many other flukicidal drugs)
128
Q

Macrocyclic lactones overview

A
  • Used in livestock, companion animal , wildlife, and humans and are available as injectable, pour-on (cattle), and oral formulations
129
Q

Why are MLs do desirable?

A
  • High potency
  • High lipophilicity (stay in tissues for a long time)
  • High therapeutic index
  • Persistence in tissues
130
Q

High potency meaning

A
  • small amount of drugs have a really big effect
131
Q

Examples of MLs

A
  • Ivermectin
  • Selamectin
  • Moxidectin
  • Doramectin
  • Milbemycins
132
Q

What defines an ML?

A
  • 16 member macrocyclic lactone ring structure and are derived from the fermentation products of various strains of Streptomycete
133
Q

What channels do MLs impact?***

A
  • Glutamate-gated chloride channels
134
Q

What is the MOA of MLs?**

A
  1. Glutamate-gated chloride channels
  2. (MLs bind to the channels which) Increases chloride conductance across cell membranes, leading to hyperpolarization
  3. Paralyses two things with flaccid paralysis:

A. Paralyzes pharyngeal pump (alters nutrient ingestion)

B. Also paralyzes somatic musculature (alters parasite to remain at the site of predilection)

135
Q

Spectrum of activity of MLs***

A
  • Insects (some lice)
  • Nematodes
  • Ectoparasites (Often used for treating various mite infections in dogs including otodectes, sarcoptes, demodex)
  • HW disease prevention: Microfilaria are very sensitive and doses required for prevention of HW disease are very low and not a problem for dogs sensitive to avermectin; this has to do with potency
136
Q

What do MLs not work against (which is why they aren’t considered broad spectrum)?***

A
  • Most cestodes and trematodes
137
Q

Variable susceptibility of helminth larvae to MLs***

A
  • In horses, encysted and developmentally arrested (hypobiotic) cyathostome larvae are the most resistant
  • In contrast, all stages of susceptible helminths in cattle - including hypobiotic larvae - are sensitive**
138
Q

Primary toxicity of MLs**

A
  • Neurotoxicity

- Can occur in all mammals, but toxicity is a matter of dose

139
Q

What is the reason behind the selective toxicity of MLs?****

A
  • Mammalian GABA gated channels are located primarily in the CNS, and these drugs (in most animals) do not cross the blood brain barrier***
  • Several dog breeds suffer neurotoxicity from macrolides at doses much lower than most dogs - these dogs are “avermectin sensitive”
140
Q

***ML Drugs that we are concerned with the most for MDR1

A
  1. Ivermectin
  2. Doramectin
  3. Abamectin
141
Q

***ML Drugs that we should be cautious with but aren’t as big of a deal with MDR1

A
  1. Milbemycin
  2. Moxidectin
  3. Selamectin
142
Q

Primary clinical signs with MLs***

A
  • These drugs increase GABA release; therefore, clinical signs are predictable and neurologic (CNS)
  • Muscle tremors, mydriasis, hypersalivation, ataxia, depression
  • Severe toxicoses can result in coma, respiratory depression, and death (may need critical care for 10 days)
143
Q

What are the first signs you usually see with ML toxicity?

A
  • Mydriasis

- Hypersalivation

144
Q

What are other adverse affects associated with MLs that are associated with the death of pathogenic and/or incidental parasitic species?

A
  • Hind limb paralysis in cattle treated during spinal cord migratory phase of Hypoderma bovis
  • SC edema and pruritus in horses with heavy infestations of Onchocerca cervicalis (uncommon)
145
Q

Can susceptible dogs that ingest feces of cows or horses treated with MLs show signs?**

A
  • Yes!
  • Active drug eliminated in feces
  • Dogs ingesting feces of sheep and horses recently dosed with MLs have developed toxicity
  • This class of anthelmintic is extremely potent compared to other classes of parasiticides
146
Q

Minimum age for MLs treatment?**

A
  • Do not administer to animals less than 6 weeks of age - immature BBB**
147
Q

Clinical use of MLs in ruminants

A
  • Ruminants - SC, oral, and topical formulations available for GI nematodes, lungworms, arthropod parasites (mites, Hypoderma bovis, Oestrus ovis, lice, cattle ticks, and screwworm)
  • Remember nematodes and ectoparasites in general
148
Q

Withdrawal time length for MLs**

A
  • Prolonged tissue residues exist
  • WIthdrawal times are fairly long (1-4 months)
  • Fairly lipophilic
149
Q

Clinical use of MLs in horses

A
  • Ivermectin and moxidectin available by either oral paste or gel formulations
  • Both are effective against GI nematodes and lungworms
150
Q

Clinical use of MLs in cats***

A
  • Topical formulations available for treating ear mites in cats***
  • Other treatments are extralabel (heartworms, demodectic mange, sarcoptic mange, GI nematodes)
151
Q

Dogs and cats licensed MLs

A
  • licensed macrocyclic lactones (oral, topical, injectable) are available for heartworm prevention in dogs and cats

Clinical Pharmacology Exam 3 (5 decks)

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