Brainscape's Knowledge GenomeTM

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


See full index

Pharmacology Exam 3 > Anti-fungals > Flashcards

Anti-fungals Flashcards

1
Q

fungal infections

A

can be superficial, subcutaneous, or systemic

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

griseofulvin

A
  • produced by Penicillium griseofulvum
  • insoluble in water
  • fungistatic
  • spectrum of action
    • ​dermatophytosis
      • effective against Microsporum, Epidermophyton, and Trichophyton
      • no effect on other fungi and bacteria
      • most common fungal disease in cats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

MOA of griseofulvin

A
  • primarily active on growing cells
  • binds to intracellular microtubules inhibiting:
    • mitosis
    • synthesis of nucleic acids and proteins
    • chitin synthesis
  • incorporated in keratin and excreted in sweat
    • not tightly bound to keratin
    • undetectable in skin after 2-3 days
  • reaches skin 4-8 hrs after admin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

griseofulvin absorption

A
  • variable
  • incomplete
  • dependent on:
    • formulation
      • microsize form
      • ultramicrosize particles
    • food: increase in absorption
      • best with fatty meal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

griseofulvin metabolism

A
  • oxidized by hepatic microsomal enzymes
  • excreted in the urine
  • metabolism 6 times faster in animals than in people
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

duration of griseofulvin treatment

A
  • at least 4 weeks for successful therapy of dermatophytosis
  • sometimes > 3 mo of continuous therapy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

monitioring griseofulvin therapy

A
  • repeat cultures
    • do not rely on physical appearance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

griseofulvin drug interactions

A
  • phenobarbital decreases absorption of griseofulvin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

formulations of griseofulvin

A
  • microsize
    • capsules
    • oral suspension
    • tablets
  • ultramicrosize
    • tablets
  • smaller size -> better absorption
    • less needed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

adverse effects of griseofulvin

A
  • GI
    • bad taste-nausea
    • vomiting, diarrhea
  • bone marrow suppression
    • cats with FIV
    • breed predilection (Persians, Himalayans, Siamese, Abyssinians)
    • CBC every 2 weeks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

griseofulvin teratogenicity

A
  • do not give to pregnant animals
  • malformations of the brain
  • skeletal malformations (spina bifida)
  • eye (cyclopia and anophthalmia)
  • miscellaneous
    • atresia ani or coli, absence of external nares and soft palate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

additional properties of griseofulvin

A
  • anti-inflammatory effects
  • suppression of allergic and irritant reactions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

amphotericin B

A
  • polyene macrolide AB
  • fungistatic/fungicidal
  • binds to sterols (fungal and mammalian)
  • disruption of integrity of membrane
    • leakage and cellular death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

spectrum of action of amphotericin B

A
  • Cryptococcosis
  • Blastomycosis
  • Histoplasmosis
  • Coccidiomycosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

administration of amphotericin B

A
  • not absorbed after oral administration
  • IV
    • dehydration increases toxicity
    • administered diluted in 5% dextrose after saline diuresis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

pharmacokinetics of amphotericin B

A
  • high protein binding
  • T1/2: 24 hours
  • metabolism
    • tissue sites
    • 10% excreted in urine
17
Q

formulations of amphotericin B

A
  • amphotericin B deoxycholate
  • several lipid formulations
    • colloidal disperson
      • lower peak serum levels
    • lipid complex
      • lower plasma and higher liver levels
  • liposomal
    • better penetration in the brain, longer half-life
18
Q

subcutaneous admin of amphotericin B

A
  • liposomal preparation
  • well tolerated
    • local irritation
  • not ideal
    • less expensive
19
Q

adverse effects of amphotericin B

A
  • thrombophlebitis
  • nephrotoxicity
    • vasoconstrition
    • direct toxicity on renal tubules
      • avoid concurrent use of other nephrotoxic drugs
  • hypokalemia
  • resistance over time
20
Q

azoles

A
  • oral
    • ketoconazole
    • itraconazole
    • fluconazole
  • topical
    • ketoconazole
21
Q

ketoconazole

A
  • insoluble in water
    • needs acidic environment for absorption
    • lipophilic
  • fungistatic/fungicidal
22
Q

ketoconazole spectrum of action

A
  • broad spectrum
    • systemic infections
    • Dermatophytosis
    • Malassezia
  • shampoo effective against Dermatophytes and Malassezia
23
Q

ketoconazole MOA

A
  • inhibition of lanosterol to ergosterol
    • affinity for fungal vs. mammalian enzyme
  • cytochrome P450 enzyme depression
24
Q

ketoconazole absorption and metabolism

A
  • oral administration
    • best given with food
  • ​peak levels in 2 hours
  • liver metabolism
  • T1/2 2 hours
  • delayed therapeutic effect (5-10 days)
  • drug interactions with drugs using cytochrome P450
25
Q

adverse effects of ketoconazole

A
  • common in cats
  • GI: nausea, V, D
  • hepatoxicity
    • usually reversible in animals
  • teratogenic
  • alopecia, pruritis, lightening coat
  • caution in geriatric animals (liver)
26
Q

itraconazole

A
  • 5-100 times more active than ketoconazole
  • increased affinity for fungal enzyme
    • fewer adverse effects
    • usually well tolerated in cats
  • broad spectrum
  • lipophilic
  • keratinophilic
  • very expensive
27
Q

metabolism and absorption of itraconazole

A
  • liver metabolism: P450 suppression
  • high concentrations reached in skin and adipose tissue
    • poor penetration in CSF, eyes
  • T1/2: dogs 8-12 hrs, cats 40-120 hrs
  • tissue levels maintained long after stopped
    • nails- 6 months
    • suitable drug for pulse therapy (don’t have to give every day)
28
Q

itraconazole administration

A
  • oral administration
    • recommended with food
    • avoid antacids (needs acidity)
    • liquid solution
    • capsules
29
Q

adverse effects of itraconazole

A
  • drug interactions
  • GI upset
  • liver toxicity
  • vasculitis at high doses
    • tip of ear, nose, tail, extremities (dogs)
30
Q

fluconazole

A
  • broad spectrum
  • highly specific for fungal enzymes
    • safest of the azoles
  • excellent penetration in the brain (eyes)
  • well tolerated in cats
31
Q

metabolism and elimination of fluconazole

A
  • good absorption
  • long T1/2
  • no liver metabolism
  • urinary excretion
  • therapeutic levels persist for 10 days after discontinuation
32
Q

terbinafine (Lamisil)

A
  • allylamine
  • lipophilic
  • keratinophilic
    • persists in nails for 2-3 mo
  • spectrum: Dermatophytosis, Malasseiza
    • not used for systemic infections
  • available in tablets, spray and cream
  • well tolerated
33
Q

MOA of terbinafine

A
  • inhibition of squalene epoxidase
    • inhibits ergosterol synthesis
      • highly specific for fungal enzyme
    • no interference with cytochrome P450

Pharmacology Exam 3 (9 decks)

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