Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology II > Lecture 34: Macrocyclic Lactones > Flashcards

Lecture 34: Macrocyclic Lactones Flashcards

1
Q

are macrocyclic lactones cidal or static

A

Cidal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Macrocyclic lactones have activity against both ___ and ___

A

Nematodes and ectoparasites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What avermectins are for use in food animals

A

Ivermectin, eprinomectin, doramectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What milbemycin is approved for use in food animals

A

Moxidectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What avermectins are for use in small animals

A

Selamectin, ivermectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What milbemycins are approved for use in small animals

A
  1. Moxidectin- dogs only
  2. Milbemycin oxime
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What spinosyn is approved for use in small animals

A

Spinosyn A/D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What avermectins is approved for use in horses

A

Ivermectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What milbemycin is approved for use in horses

A

Moxidectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Topical macrocyclic lactones are more effective against ___

A

Biting lice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What macrocyclic lactones are effective against horn flies in ruminants

A

Ivermectin and eprinomectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does ivermectin tx in pigs

A

GI roundworms, lungworms, lice, sarcoptic mange

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is ivermectin and Moxidectin use for in horses

A

GI roundworms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Ivermectin in horses has better activity against ___

A

Gastrophilus intestinalis (bots)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Moxidectin in horses has better activity against ___

A

Cyanthostomum (GI round worms)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is ivermectin use for in dogs

A
  1. Prevention of D. Immitis
  2. Generalized demodicosis, Cheyletiella (zoonotic), sarcoptes scabieie, otodectes, pneumonyssoides spp
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is selamectin used for in dogs

A
  1. Prevention of D. Immitis
  2. Fleas
  3. Otodectes spp
  4. Sarcoptes scabiei
  5. Dermeacentor variabilis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is milbemycin oxime effective against in dogs

A
  1. D. Immitis prevention
  2. GI round worms
  3. Hookworms (zoonotic)
  4. Whipworms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is Moxidectin used for in dogs

A
  1. Prevention D. Immitis
  2. Hookworms only
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is spinosad effective against in dogs

A

Fleas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

All macrocyclic lactones are effective against stage __ and __ larvae of D. Immitis

A

Stage 3 and 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is ivermectin used for in cats

A

Prevention of D. Immitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is selamectin used for in cats

A
  1. Prevention of D. Immitis
  2. Fleas
  3. Otodectes spp
  4. T. Cati
  5. A tubaeforme (hookworms)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is milbemycin oxime effective against in cats

A
  1. D. Immitis prevention
  2. GI roundworms
  3. Hookworms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is spinosad used for in cats

A

Fleas (dosing is higher than in dogs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is class 1 heart worm disease on severity scale

A

Asymptomatic, positive antigen test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is class 2 heart worm disease on severity scale

A

Moderate pulmonary damage, coughing, exercise intolerance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is class 3 heart worm disease on severity scale

A

right CHF, cor pulmonale, syncope, anemia, cache is

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is class 4 heart worm disease on severity scale

A

= caval syndrome
Shock, DIC, jugular distention, mitral regurgitation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What classes on severity scale for heart worm disease can be treated with drugs

A

1-3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What class on severity scale of heart worm needs sx intervention

A

Class 4

32
Q

What species does microfilaria rarely circulate and host is often able to mount an immune response and kill worms

A

Cats

33
Q

What larval stages are macrocyclic lactones effective against

A

Only L3 and L4, no adults

34
Q

What stage of heart worm, worms is melarsomine effective against

A

Adult females, antigen positive

35
Q

What is the split dose tx for heart worm

A
  1. Start on avermectin monthly
  2. Reduce activity- cage rest
  3. 1 month later start doxycycline
  4. 1 month after that 1st melarsomine dose
  5. 1 month after that 2nd and 3rd melarsomine doses 1 day apart
36
Q

What is wolbachia

A

Gram - rickettsia bacteria that infects heart worms

37
Q

What is wolbachia associated with

A
  1. Survival of filaria
  2. Production of filaria
  3. Infectivity of filaria (L3)
  4. Pulmonary and renal inflammation via wolbachia surface protein
38
Q

What drug is used to target wolbachia in heart worm

A

Doxycycline

39
Q

Doxycycline is given to target wolbachia 30 days prior to ___

A

Melarsomine

40
Q

What is the critical role/ purpose of doxycycline

A

Reduces worm burden prior to adulticide so decreases risk of thrombosis and inflammatory reaction to dead worms

41
Q

What is melarsomine labeled for

A

D. Immitis >5 months in dogs in stable Class 1-3 disease

42
Q

Melarsomine can only be used in __ settings

A

Hospital

43
Q

Melarsomine is absolutely contraindicated in dogs with ___

A

Caval syndrome

44
Q

What are some risks associated with melarsomine

A
  1. Pulmonary thromboembolic events
  2. Hyperventilate reactions
45
Q

Melarsomine has increased risk of adverse effects in dogs if given __ or ___

A

IV or SQ injections

46
Q

What are some adverse effects of melarsomine in dogs

A
  1. Injection site inflammation
  2. Coughing/gagging
  3. Lethargy
  4. Inappetence
  5. Fever
  6. Lung congestion
  7. Vomiting
  8. Paresis/ paralysis
47
Q

Melarsomine is very toxic in what species

A

Cats

48
Q

What is the PD of macrocyclic lactones

A
  1. Noncompetitive agonist of glutamate activated chloride channels—> flaccid paralysis of somatic musculature and pharyngeal pump
  2. Agonist of GABA receptors found on ventral nerve cord and head of nematodes
49
Q

Glutamate is a __ neurotransmitter in nematodes

A

Inhibitory

50
Q

Macrocyclic lactones also inhibit the ___in female nematodes

A

Reproductive tract

51
Q

Macrocyclic lactones are highly lipophilic drugs that are poorly absorbed in ___GI tract

A

Ruminant

52
Q

Ivermectin bioavailability is __% in cattle, but __% in doings

A

25-33%, 95%

53
Q

Selamectin bioavailability is __% in dogs, but __% in cats

A

5%, 75%

54
Q

Macrocyclic lactone plasma concentration is = to ____concentration and therefore effective against ___

A

Skin concentration
Effective against ectoparasites

55
Q

T or F: macrocyclic lactones have a wide distribution

A

True

56
Q

Macrocyclic lactones rapidly distributes to ___which serves as a depot and slows elimination

A

Adipose tissue

57
Q

Macrocyclic lactones are extensively distributed to __ and ___, and permeates ___

A

Lung, skin, permeates BBB

58
Q

Macrocyclic lactones are metabolized by the ___in sheep and cattle

A

Liver

59
Q

Macrocyclic lactones are eliminated via

A

95% fecal, 5% urine

60
Q

20% of doramectin and metabolites undergo ___recirculation in sheep

A

Enterohepatic

61
Q

Avermectins are eliminated in the ___ and therefore use is restricted to ___animals

A

Milk, non-lactating animals

62
Q

What avermectins are not eliminated in milk and which one can be used in lactating cows

A
  1. Eprinomectin
  2. Moxidectin- use in lactating cows
63
Q

What is required to move macrocyclic lactones out of tissues and is therefore contraindicated in what breed

A

P-gp, contraindicated in collies

64
Q

What gene is associated with P-gp

A

MDR1

65
Q

Collies have what deletion resulting in MRD1 mutation

A

4 base pair inactivating deletion of ABCB1-1

66
Q

What are some adverse effects of macrocyclic lactones in ABCB1-/-

A

Vomiting, tremors, ataxia, myriads is, blindness, seizures

67
Q

Ivermectin is toxic at <___dose in ABCB1-/- dogs

A

<2x normal dose

68
Q

What are some safer alternate macrocyclic lactones to be used in collies

A
  1. Selamectin (6.5x normal dose)
  2. Milbemycin oxime (2x normal dose)
69
Q

Combination of ivermectin with ___increased BBB permeability and increased toxicity

A

Spinosad (flea tx)

70
Q

In all species with any of the macrocyclic lactones ___reactions may occur with large worm burdens

A

Hypersensitivity reactions

71
Q

What is the frontline approach to prevent hypersensitivity reactions to macrocyclic lactones due to large worm burden

A

Doxycycline, steroids

72
Q

Organisms resistant to macrocyclic lactones have mutation or increased expression of ___

A

P-gp

73
Q

What species has been found to be ivermectin resistant in sheep/goats

A

Haemochus

74
Q

What species have been found to be ivermectin resistant in cattle

A

Trichostrongylus

75
Q

What are some treatment options for ivermectin resistant strains

A
  1. Verampil- reverses P-gp
  2. Moxidectin currently retains activity

Pharmacology II (34 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions