Brainscape's Knowledge GenomeTM

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


See full index

pharm 2 mod 4: fungals/microbials > antifungals > Flashcards

antifungals Flashcards

1
Q

what type of fungal infections are life threatening

A

systemic infections

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

what populations are often affected by fungal infections

A

immunosuppressed
chronic immune suppression
undergoing chemotherapy
HIV/AIDS
etc

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

what are the superficial fungal infections

A

pityriasis versicolor
tinea nigra

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

what are cutaneous fungal infections

A

dermatophytosis (skin, hair and nails) (tineas)
candidiasis of skin (breast, armpits, inguinal folds)

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

what are subcutaneous fungal infections

A

sporotrichosis (rose-gardeners)
chromomycosis

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

what are systemic fungal infections

A

coccidioidomycosis
histoplasmosis
blastomycosis
cryptococcosis
systemic candidiasis
aspergillosis
zygomycetes (mucorales)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the different categories of antifungal drugs

A

Polyenes
Zadoles
Echinocandins
allylamines
other

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

what are the polyene antifungal medications

A

amphotericin B
Nystatin (potent)

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

what are the Zoles antifungal medications

A

clotrimazole
ketoconazole
fluconazole
itraconazole
posaconazole
posaconazole
voriconazole

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

what are echinocandin medications

A

caspofungin

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

what are allylamines

A

terbinafine

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

what are the other antifungal drugs

A

flucytosine
griseofulvin

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

what is the MOA for amphotericin B

A

lipophilic rod-like molecule disrupts fungal cell wall synthesis by binding to sterols, primarily ergosterol, leading to formation of pores in the cell membrane. K+ leaks out of cell resulting in cell death.

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

what is amphotericin B produced by

A

streptomyces nodosus

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

when is amphotericin B used

A

treatment of severe invasive fungal infection
widest spectrum of activity of all antifungals
rapid onset
resistance is rare

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

what are the pharmacokinetics of amphotericin B

A

metabolism poorly understood
poor PO absorption. Used IV - wide tissue distribution
little CSF penetration; intrathecal sometimes used
low TI
Nephrotoxicity - azotemia due to dose-dependent decrease in GFR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the AE of amphotericin B

A

infusion related reactions:
fever and rigors
decreased incidence following multiple doses
pre-medicate with Tylenol or Benadryl recommended
may treat rigors with low-dose meperidine
Nausea/vomiting, anemia, phlebitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is flucytosine

A

5-FC
synthetic pyrimidine analog (false nucleotide)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the MOA for Flucytosine

A

inhibits thymidylate synthase and incorporates into fungal RNA disrupting nucleic acid and protein synthesis
NOT used as monotherapy; resistance too high

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is the spectrim of activity for flucytosine

A

used in combo with ampotericin B (synergistic) for tx of systemic mycoses and meningitis caused by cryptococcus and candida spp.
used in combo with itraconazole for treatment of chromoblastomycosis infections

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

What needs to be monitored when using amphotericin B

A

K+, Mg++; replete aggressively in the presence of decreased GFR

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

What are the pharmacokinetics of Flucytosine

A

good PO absorption, penetrates CSF
dose adjustment required in renal impairment

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

what are the AE of flucytosine

A

reversible neutropenia, thrombocytopenia
dose-related bone marrow suppression
reversible hepatic dysfunction
more common: GI upset, N/V, diarrhea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the two groups of azoles

A

imidazole and triazoles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are the imidazoles

A

ketoconazole
miconazole
clotrimazole

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

what are the traizoles

A

fluconazole
itraconazole
voriconazole
posaconazole

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

what is the MOA for the imidazole

A

inhibit C-14 alpha-demethylast (CYP450 enzyme), which block the demethylation on lanosterol to ergosterol thereby disrupting membrane structure

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

which of the imidazoles are too toxic for systemic use and are topical use only

A

miconazole and clotrimazole

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

what is ketoconazole

A

imidazole - may be used systemically (but systemic use replaced by newer triazoles)

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

what is the MOA for ketoconazole

A

inhibit C-14 alpha-demethylase - decrease syntehsis of ergosterol thereby disrupting membrane strucure
may be used sysetmically
should not be used with amphotericin B

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

what is the spectrim of activity of ketoconazole

A

candida, histoplasma, blastomyces, coccidioides but NOT aspergillus species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what are the pharmacokinetics of ketoconazole

A

topical and PO formation available
requires gastric acid for dissolution and absorption
does NOT penetrate CSF
endocrine effect: inhibit human gonadal and adrenal steroid homrone synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what are the AE of ketoconazole

A

GI upset
hepatitis rare - d/c if raising LFTs
gynecomastia, decreased libido, menstrual irregulatiteis
drug interactions: CYP450 metabolized drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

when is ketoconazole contraindicated

A

Pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the MOA for triazoles

A

inhibits synthesis of cellmembrane via fungal CYP 450 inhibition similar to ketoconazole, however, it does not interefere with the mammalian CYP 450 enzymes involvved in synthesis of other steroid hormones - no endocrine side effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what is the spectrim of activity of fluconazole

A

candida, cyrptococcus neoformans, coccidiomycosis; no activity against aspergillus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what is the pharmacokinetics of Fluconazole

A

PO/IV, not dependent on gastic acid
Good CSF penetration
dose adjust in renal impairment

38
Q

what are the AE of fluconazole

A

N/V/rashes, alopecia, hepatitis is rare

39
Q

what are the contraindications for fluconzaole

A

teratogenic- should not be used in pregnancy

40
Q

what is the spectrum of activity for itraconazole

A

broad: drug of choice for histoplasmosis, blastomycosis, sporotrichosis

41
Q

what are the pharmacokinetics of itraconazole

A

good PO availability but requires gastic acid for absoprtion; no IV formulation
metabolized in liver
no dose-adjustment in renal impairment
dose not penetrate CSF well

42
Q

what are the AE of itraconazole

A

N/V, rash, HA
HTN, Hypokalemia, edema
rarely hepatitis
chronic therpay can cause alopecia
potential drug-drug interactions: warfarin, statin, phenytoin
contra: teratogenic.
black box warning: CHF

43
Q

what is the MOA for caspofungin

A

echinocandins
inhibits B (1,3) - D- Glucan synthase, an enzyme involved in fungal cell wall synthesis

44
Q

what is the spectrum of activity for caspofungin

A

invasive aspergillus infection (2nd line agent)
- vericonazole 1st line agent
candidal infections:
-c. glabrata candidemia
zole-resistance candida esophagus

45
Q

what is capsofungin not active against

A

zygomycytes and crypotococcus noeformans

46
Q

what are the AE of echinocandins

A

generally well tolerated
histamine reaction with infusion - pretreat with benadryl
drug-drug interactions: cyclosporine, tacrolimus, rifampin
CNS penetration is poor

47
Q

what is the MOA forNystatin

A

binds to ergosterol’ similar mechanisms of amphotericin B
too toxic for systemic use - never used IV

48
Q

what is grieofluvin

A

Mechanism: inhibits mitosis
used for dermatophytic nail infections - accumulates in keratin-containing tissues
treatment may be required for 6-12 months

49
Q

what are the drug to drug interactions with grieofulvin

A

induces CYP450 enzymes; increases rate of metabolism of other drugs including anticaogulants
avoid alcohol during therapy

50
Q

what is terbinafine

A

mechanism: inhibits cell wall synthesis by inhibiting fungal squalene epoxidase - decreases the synthesis of ergosterol

51
Q

where does terbinafine accumulate

A

skin, nails and fat - drug of choice for onychomycosis and dermatophytic infections

52
Q

what are the SE/AE of terbinafine

A

contraindicated in nuring mothers - accumulates in breast milk
ARDs: hepatotoxicity - LFTs at baseline

53
Q

What is coccidioimycosis

A

southwest US, aerosolized spores from soil
pulmonary disease
synovitis
hepatospenomegaly
meningitis leading to hydrocephalus

54
Q

what are the treatment options for coccidioidomycosis

A

fluconazole or itraconazole, amphotericin B if severe/dissminated

55
Q

what is Histoplasmosis

A

ohio, missouri, and mississippi river valeys
bird droppings in damp soil, bats
pulmonary disease to disseminated disease
disseminated form includes GI, cardiac, ocular and CNS effects

56
Q

what is the treatment of choice for histoplasmosis

A

itraconazole

57
Q

what is blastomycosis

A

great lakes region, inhalation of spores
pulmonary disease
skin lesions: sharply demarcated, grey to violet verrucal lesions, irregular borders
lytic bony lesions
prostatitis

58
Q

what is the treatment of choice for blastomycosis

A

itraconazole
consider fungal infection in pneumonias not responding to antibiotics

59
Q

what is Aspiergillosis

A

pulmonary disease most common
increased risk if have asthma or COPD
cavitary lesions
consider chronic form in patients whose respiratory symptoms do not respond to prolonged antibiotic therapy

60
Q

what is the treatment options for aspergillosis

A

vericonazole, posaconazole (not first lien), capsofungin, amphotericin B

61
Q

what is zygomycetes

A

rhizopus fungus, aggressive infections
nasopharynx of immunocompromised patients

62
Q

what are the treatment options for zygomycetes

A

prompt surgical debridement
posaconazole, amphotericin B

63
Q

what are antiprotozoal durgs

A

trimethoprim-sulfamethoxazole
metronidazole

64
Q

what aare the antihelmintic drugs

A

albendazole
pyrantel pamoate
ivermectin
praziquantel

65
Q

What is the MOA for metronidazole

A

activated by anaerobes to metabolites that damage DNA - the nitro group of metronidaazole serves as an electrol acceptor and forms toxic metabolite that disrupt DNA helical structure leading to cell death

66
Q

what are the uses for metronidazole

A

amebiasis, giardiasis, tricomoniasis (and anaerobic bacterial infections)

67
Q

what is considered a tissue agent and is co-administered with luminal agent, paromomycin

A

metronidazole
-asymptomatic patient may be treated with intraluminal agent alone

68
Q

what are the pharmacokinetics of metronidazole

A

metabolized in liver- accumulates in aptients with severe hepatic disease; excreted in urine

69
Q

What are the ARDs of metronidazole

A

GI disturbance (N/V), metallic taste, seizure, neuropathy, disulfiram (antabuse) effect with alcohol

70
Q

what are contraindications for metronidazole

A

pregnancy, breast feeding, recent us of disulfiram

71
Q

what are alternative therapies for metronidazole

A

tinidazole, ornidazole, and nitrazoxanide

72
Q

What is the MOA for Bactrim

A

combination of TMP-SMX provides sequential, and thus synergistic blockade of FOLATE pathway: which leads to inhibition of thymidines synthesis

73
Q

what is bactrim used for

A

cyclospora and isospora infections

74
Q

what are the ARDS for bactrim

A

many potention
Rash, SJS, kernicterus, hemolysis in G6PD-deficiency patients; may lead to bone marrow suppression and anemia, renal impairement, hepatotoxicity

75
Q

when should bactrim be avoided

A

patients with renal disease
drug-drug interactions with: warfarin, phenytoin, methotrexate
contra: newborns (<2months) and pregnancy

76
Q

what is the primary treatment for nematodes (roundworms)

A

albendazole

77
Q

what is the treatment for cestodes (tapeworms)

A

praziquantel

78
Q

what is the treatment for trematodes (flukes)

A

praziquantel

79
Q

what is the MOA for albendazole

A

binds to microtubules in the intesting and tegmental worm and larvae; impaired glucose uptake - glycogen depletion - degeneration of ER and mitochondria, release of lysosomes, and depletion of ATP/energy causing worm death

80
Q

what are the uses for albendzaole

A

broadly effective against nematode infections (round worms)

81
Q

what are the ARDS of albendazole

A

HA, elevated LFTs
rare: GI, alopecia
very rare: liver failure, myelosuppression, seizure
Contra: pregnancy

82
Q

what is the moa pyrantel pamoate (OTC)

A

causes release of acetylcholine and inhibits cholinesterase; acts as a depolarizing neuromuscualr blocker, spastic PARALYSIS and release of helminths

83
Q

what are the uses for pyrantel pamoate

A

NOT Preferred - new agents available
alternate to albendazole therapy for enterobius vermicularis (pin worms) infection

84
Q

what are the ARDs with pyrantel pamoate

A

rare HA, dizziness, GI distress

85
Q

what is the MAO for praziquantel

A

increases cell permeability to Ca2+ in schistosomes - strong contractions and paralysis of worm muscularture which leads to detachement and dislodgement and death

86
Q

what are the uses of praziquantel

A

cestodes (tapeworms) and trematodes (flukes)

87
Q

what are the ARDS of praziquantel

A

abdominal pain, dizziness, drowsiness
pts with cerebral cysticercosis experience CNS SE HA, seizures - from the death of parasites
CYP450

88
Q

what is the MAO for ivermectin

A

binds and activates glutamate - gated chloride channels (GluCls) in invertebreate nerve and muscle cells; - hyperpolarization and death of helminth - does not cross BBB

89
Q

what is the use of ivermectin

A

strongyloidiasis and onchocerviasis (“river blindness”); also used topically for head lice

90
Q

what are the ARDS for ivermectan

A

neurotoxicity (CNS depression, ataxia) froma ctivation of GABA-nergic synapses; some cutanous effects
CI: prenancy, meningitis

pharm 2 mod 4: fungals/microbials (3 decks)

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