Antifungals, antimycobacterials, antivirals Flashcards

(122 cards)

1
Q

What’s a genus of bacteria that includes many species of pathogens?

A

mycobacterium

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

What are the targets of antimycobacterials?

A

enzymes that mycobacteria use to build their cell walls

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

How are mycobacteria different than typical bacteria?

A

easier to control but harder to treat because they replicate slower.
CAN exist in a dormant state which makes them resistant to nearly all abx

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

What’s the standard treatment in active mycobacterial disease?

A
  • Rifampin
  • Isoniazid
  • Pyrazinamide
  • Ethambutol

Note: takes weeks to get susceptibility results

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

How does isoniazid work?

A
  • bactericidal
  • inhibits mycolic acid synthesis!
  • effective against active AND dormant TB
  • acts as a weak MAO-I (careful with SSRI/SNRI)
  • alters pyridoxine metabolism (give B6 to all patients)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the two most important drugs for TB?

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

What is isoniazid active against?

A

M. tuberculosis and M. kansasii

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

How is isoniazid clinically utilized?

A

mycobacterial infections

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

When is isoniazid your DOC?

A

latent TB, active TB

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

What are ADRs of isoniazid?

A

hepatotoxicity, peripheral neuropathy (use pyridoxine), hemolysis in G6PD deficiency

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

What are examples of rifamycins?

A
  • rifampin
  • rifabutin
  • rifapentine
  • rifaximin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What’s the MOA of rifamycins?

A
  • bactericidal
  • Inhibits DNA-dependent RNA polymerase
  • very good oral bioavailability
  • resistance emerges when drug is used alone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What should you always screen for drug ineractions?

A

rifamycins – extremely potent CYP450 inducers!!
also, reduced effectiveness of oral contraceptives

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

What are rifamycins GOOD for?

A

mycobacteria

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

What are rifampins moderate for?

A

staph, acinetobacter, enterobacterciae

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

What are rifamycins utilized for?

A

mycobacterial infections – usually in combo w/ deep seeded “typical” bacterial infections (MRSA) or if prosthetic material

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

When is rifamycin your DOC?

A

TB = tuberculosis, MAC = mycobacterium avium complex

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

What are ADRs of rifamycins?

A

orange-red colored secretions (urine, tears)

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

Do rifamycins have DIs?

A

many due to enzyme induction

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

What’s the MOA of pyrazinamide?

A
  • bacteriostaticuncertain but requires bioactivation via hydrolytic enzymes to form pyrazoic acid
  • shortens duration 9m - 6m

NOT pyridoxine
AVOID IN PREGNANCY

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

When are pyrazinamides clinically active?

A

M. tuberculosis

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

When are pyrazinamide clinically utilized and is your DOC?

A

active TB

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

What are the ADRs of pyrazinamide?

A

polyarthralgia (40%), hyperuricemia, mylagia, maculopapular rash, porphyria, photosensitivity

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

What’s the MOA of ethambutol?

A
  • bacteriostatic
  • inhibits formation of arabinoglycan, component of mycobacterial cell wall
  • only 1st 2 months of tuberculosis therapy
  • **NOT recommended in children <5yo **
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
When is ethambutol clinically active and utilized?
* M. tuberculosis, M. avium-intracellulare, M. kansaii * active TB and MAC infections
26
What are ADRs of ethambutol?
* dose-dependent visual disturbances * headache * confusion * hyperuricemia * peripheral neuritis * difficulty deferentiating from red and green
27
What are the increase of systemic fungal ifnections a consequence of?
medical advancement
28
What are types of moulds?
aspergillus (a. fumigatus, mucor spp, rhizopus spp) dermatophytes
29
What are types of yeasts?
candida (C.albicans) cryptococcus (C.neoformans, C. gattii) Malassezia (M. furfur)
30
What are dimorphic fungi?
histoplasma capsulatum coccidioides immitis sporothirix schenkii blastomyces
31
Imidazoles: COMET-K
Clotrimazole Oxiconazole Miconazole Econazole Tioconazole Ketoconazole
32
Triazoles: FIT VIP
Fluconazole Itraconazole Teraconazole Voriconazole Isavuconazole Posaconazole
33
Allyamines: TAN
Terbinafine Amorolfin Naftifine
34
Echinocandins: MAC
Micafungin Anidulafungin Caspafungin
35
What are examples of polyenes?
amphotericin B, nystatin
36
What is the MOA of polyenes?
* fungicidal/fungistatic (dependent) * binds to ergosterol in fungal cell membranes, forming leaky pores
37
What's used to decrease polyene side effects?
lipid formulations and different dosing dependent
38
What are ADRs of polyenes?
nephrotoxicity, infusion reactions (chills, fever, muscle spasms, hypotension), electrolyte abnormalities (hypokalemia)
39
When do polyenes have good coverage?
candida and aspergillus, cryptococcus neoformans, dimorphic fungi, molds
40
When do polyenes have moderate coverage?
zygomycetes
41
When are polyenes clinically utilized?
unknown fungal infections, use for candidiasis and aspergillosis (less often with newer/safer agents)
42
When are polyenes your DOC?
cryptococcal meningitis and serious dimorphic fungi and mold infections
43
What are DIs with polyenes?
nephrotoxic drugs (additive)
44
What are examples of azoles?
fluconazole, itraconazole, voriconazole, ketoconazole
45
What's the MOA of azoles?
* fungicidal and fungistatic (dependent) * inhibits fungal P450 dependent enzymes blocking ergosterol synthesis * mainstays of antifungal therapy
46
What's the ADRs of azoles?
hepatotoxicity, Qtc prolongation, rash, upset stomach
47
What DIs do azoles have?
many -- inhibits CYP450
48
Which is the only azole with significant utility in candiduria?
fluconazole
49
What's fluconazole have good and moderate clinical activity?
good = candida albicans, candida tropicalis, candida parapsilosis, candida lusitaniae, cryptococcus neoformans, coccidiodes immitis moderate = candida glabrata
50
When is fluconazole utilized clinically?
candidiasis, cryptococcal meningitis, cocciodal meningitis orally or IV
51
When is fluconazole your DOC?
many susceptible fungal infections, invasive and non invasive candidiasis (NOT candida krusei)
52
Why are only oral formulations availble of itraconazole?
caps
53
When is itraconazole good and moderate clinically?
good = candida albicans, c. parapsilosis, c. tropicalis, c. lusitaniae, cryp. neoformans, aspergillus, dimorphic moderate = candida glabrata and candida krusei
54
When is itraconazole clinically utilized?
* dermatomycosis * histoplasmosis * blastomycosis * coccidiomycosis * sporotrichosis
55
When is itraconazole your DOC?
histoplasmosis and blastomycosis
56
What is recommended with voriconazole?
administer 1 hour before or after a meal -- 90% oral bioavalability this way. also, monitor drug levels because of varaible nonlinear elimination
57
When does voriconazole have good and moderate activity?
good = candida albicans, candida lusitaniae, c. parapsilosis, c. tropicalis, c. krusei, cryptococcus neoformans, aspergillus moderate = candida glabrata, candida albicans that are flu-resistant, fusarium
58
When is voriconazole clinically utilized/ yoru DOC?
invasive aspergillus, other molds
59
What's important to remember about posaconazole?
Take PO forms with food or soda, and also suspension and tab that have different dosing
60
When does posaconazole have good or moderate activity?
good = candida albicans, candida lusitaniae, c. parapsilosis, c. tropicalis, c. krusei, aspergillus, zygomycetes, other moulds, dimorphic fungi moderate = fusarium, c. glabrata
61
When is posaconazole clinically utilized?
fungal infection prophylaxis, zyomycosis, resistent oropharyngeal candidiasis, fungal infections
62
When is posaconazole your DOC?
prophylaxis for invasive aspergillosis and candidiasis
63
What are examples of echinocandins?
caspofungin, micafungin, anidulafungin *all IV only*
64
What's the MOA of echinocandins?
fungalstatic and fungicidal depending inhibit glucan syntase, decreasing fungal cell wall synthesis
65
What are the ADRs of echinocandins?
excellent safety profile -- GI distress, flushing from histamine, rare hepatotoxicity
66
What are DIs of echinocandins?
cyclosporine increase (Caspofungin) and increase sirolimus (micafungin)
67
When do echinocandins have good or moderate activity?
Good = candida albicans, c. glabrata, c. lusitaniae, c. parapsilosis, c. tropicalis, c. krusei, aspergillus moderate = candida parapsilosis, dimorphic fungi
68
When are echinocandins clinically utilized?
invasive candidiasis, esophageal candidiasis, empiric therapy for fungal infections
69
When are echinocandins your DOC?
invasive candidiasis
70
What can viruses cause on the host cell?
death, transformation (papillomaviruses), latent infection
71
Why do antiviral agents have limitations?
limited effectiveness at the point of symptoms
72
What are antivirals for herpes?
acyclovir (IV/PO/topical), valacyclovir (PO), famciclovir (PO) val and fam are prodrugs!
73
What are MOAs for antivirals for herpes?
activated by viral thymidine kinase to forms that inhibit viral DNA polymerase
74
What are ADrs for antivirals of herpes?
nephrotoxicity (must hydrate and renally dose) , CNS effects Consider oral forms causing GI issues
75
How are herpes antivirals good and moderately active for?
good = HSV-1 and HSV -2 moderate = varicella zoster
76
When are antiviral for herpes your DOC?
severe or difficult to treat HSV infections, severe HSV outbreaks among HIV patients (acyclovir), HSV-2 infections/prevention, VZV
77
How do you dose acyclovir?
based on ideal body weight
78
What are examples of neuraminidase inhibitors?
oseltamivir (PO) and zanamivir (inhaled)
79
What is the MOA of neuraminidase inhibitors?
prevents viral neuraminidase enzymes from releasing new virions from the host cell, preventing replication most effective starting EARLY
80
When should neuraminidase inhibitors be started?
within 2 days of symptom onset, decreases ~1 day
81
What influenzas are neuraminidase inhibitors good for?
A and B
82
When are neuraminidase inhibitors your DOC?
Influenza prophylaxis and influenza infection w/ symptoms <2 days
83
What are ADRs of neuraminidase inhibitors?
oseltamivir: GI symptoms, HA and fatigue can also occur when drug is given for a longer period zanamivir: pulmonary adverse effects, avoid w/ asthma
84
How does HIV infect the body?
infects lymphocytes and macrophages and results in progressive decline of CD4 T-cells -- leads to opportunistic infections
85
How is HIV transmitted?
sexually, perinatally, breastfeeding, IV drugs
86
What are the 3 phases of HIV disease?
1. Acute seroconversion -- fever, flu-like illness, lymphadenopathy, rash, several weeks 2. asymptomatic HIV -- few or no signs/symptoms but CD4 T cell count declines...may last a few years to a decade 3. AIDS -- immune system damaged enough for significant opportunistic infections, <200 CD4 T cell count
87
What was the first antiretroviral drug for HIV?
zidovudine (AZT) in 1987
88
What is ART or HAART?
* current treatment regimen with 3-4 drugs * suppress viral replication and restore number of CD4 cells * ART recommended for all HIV infected indviduals * significantly decreases morbidity and mortality
89
What should you always do with HIV treatment?
* combo therapy = reduces likelihood of drug resistance, slows disease progression * individualized treatment * **always check for DIs**
90
What are some NRTIs (nucleotide reverse transcriptase inhibitors)?
abacavir, emtricitabine, lamivudine, tenofovir, zidovudine
91
What's the MOA of NRTIs?
inhibit HIV reverse transcriptase after phosphorylation by cell enzymes
92
What are ADRs of NRTIs?
* peripheral neuropathy * GI effects * bone marrow suppression * **hypersensitivity (abacavir)** * lactic acidosis, hepatic steatosis, pancreatitis * nephrotoxicity
93
What is generally the backbone of most ART regimens?
2 NRTIs -- renally dosed
94
What else can NRTIs be used for?
Hep B virus (tenofovir, emtricitabine, lamivudine)
95
What are examples of NNRTIs (non-nucleotide)?
efavirenz, nevirapine, etravirine, rilpiverine
96
What's the MOA of NNRTIs?
inhibit same enzyme as NRTIs but different mechanism
97
What are ADRs of NNRTIs?
* Cns problems - EFV * rashes * hepatotoxicity - NVP * hypersensitivity w/ flu like sxs, fever, juandice, ab pain * lipohypertrophy "buffalo hump" * hyperlipidemia - EFV and NVP * EFV + pregnancy category D
98
Why is it essential to stick to your HIV regimen?
easily can develop resistance
99
What are some protease inhibitors?
atazanavir, ritonavir (boosting), ritonavir (full dose), lopinavir
100
What's the MOA of protease inhibitors?
Inhibit viral protein processing by binding to site of protease activity on HIV
101
What are ADRs of protease inhibitors?
* cardiovascular (MIs and strokes) * severe GI: take w/ food * hepatotoxicity * liphypertrophy * nephrotoxicity
102
What are DIs with protease inhibitors?
MANY - strong CYP450 inhibitors
103
Protease inhibitors are ____ resilient to development of resistance
more
104
Protease inhibitors did what with highly active antiretroviral therapy
began the era -- major impact on prolonging life span
105
True or false: only ATV of protease inhibitors is used w/o booster
true
106
What are examples of integrase inhibitors?
raltegravir, elvtegravir, dolutegravir
107
What's the MOA of integrase inhibitors?
block integration of proviral gene into human DNA newest class of ART and regarded as 1st line therapy
108
What are ADRs/ DIs of integrase inhibitors?
pretty well tolerated -- increases creatine kinase, LFT, GI...minimal DIs
109
What's a CCR5 inhibitor?
maraviroc
110
Whats the MOA of CCR5 inhibitors?
inhibits CCR5 receptors on cell membrane preventing entry of HIV into cell
111
What are ADRs of CCR5 inhibitors?
hepatotoxicity -- black box warning muscle and joint pain diarrhea
112
What are DIs of CCR5 inhibitors?
metabolized by CYP450 -- dosage adjustments are required
113
True or false: you do not need genetic testing to start Maraviroc
false
114
What do you need to test for Maraviroc?
HIV tropism w/ trofile test
115
What must you be to use maraviroc?
CCR5-positive **do not use with dual/mixed or CXCR-4 tropic HIV-1**
116
What is paxlovid?
Drug for COVID-19 that's combo but in separate tablets (Nirmatreivir and ritonavir) reduces symptoms by 2-3 days
117
What's the MOA of nirmatreivir and ritonavir (paxlovid)?
protease inhibitor binding to enzyme preventing replication
118
Are there any DIs with paxlovid?
Yes - a lot.
119
What is remdesivir?
* inpatient or outpatient IV * for covid or ebola * RNA polymerase inhibitor * may interact w/ hydroxychloroquine * can cause elevated liver enzymes, PT increase, renal impairments
120
What is malnupiravir?
* oral COVID med * within 5 days of symptoms * acts as ribonucleoside analog for viral RNA polymerase increasing mutations * diarrhea, nausea, dizziness
121
Can antiviral medications treat viral hepatitis?
yes -- NRTIs, NPIs, interferons, nucleoside analogues
122
What's a serious potential side effect of isoniazid?
peripheral neuropathy from lack of B6