Antimicrobials

Question 1

1. Which condition do you use Amphotericin B? Amphotericin B MOA?
2. When would you add an antifungal adjuvant? The antifungal adjuvant MOA?

Answer 1

1. Severe systemic mycotic infection. (binds ergosterol to allow leakage)
2. Cryptococcal meningitis add flucytosine (blocks conversion of 5-FU by cytosine deaminase)

Question 2

Adverse effects of using Amphotericin B

Answer 2

AAmPHotericiN

Anemia, **Arrhythmia, Makes u feverish, **Phlebitis, Hypotension, -oterici Nephrotoxicity B

Question 3

Which condition do you use nystatin? MOA?

Answer 3

Oral candidiasis, vaginal/pelvic candidiasis. (binds ergosterol to allow leakage)

Question 4

Which condition do you use Azoles? MOA? Key adverse effects?

Answer 4

Most local, less serious systemic infection. (inhibit 14-a-demethylase that forms ergosterol from lanosterol)
MOA: gynecomastia (esp ketoconazole)

Question 5

Which condition do you use terbinafine? MOA?

Answer 5

Dermatophytoses (inhibits Squalene epoxide to form lanosterol from squalene) (strong TERBIN good against SQUAL)

Question 6

Which condition do you use Griseofluvin? MOA? Key complications?

Answer 6

oral treatment for severe superficial infections, dermatophytes. (MOA: interferes with microtubule a/b-tubulin dimer)
A/E: teratogenic,carcinogenic, CNS symptoms, **disulfiram-like rxn

Question 7

What do you use to treat influenza? Which mechanisms does it prevent? What is the point of consideration while prescribing this drug?

Answer 7

Zanamivir, oseltamivir
MOA: inhibit influenza neuraminidase to prevent release of progeny virus.
Use the drug within 48 hr of sx

Question 8

When do we decide to use acyclovir, famciclovir, ganciclovir?

Answer 8

Acyclovir: VZV, HSV

famciclovir: VZV
ganciclovir: CMV

Question 9

A/E of acyclovir and famciclovir. Difference between the MOA of both

Answer 9

crystal uropathy.
Both inhibits viral DNA polymerase.
Acyclovir via chain termination, famciclovir via act as competitive inhibitor for viral dGTP

Question 10

A/E of ganciclovir

Answer 10

bone marrow suppression, nephrotoxicity

Question 11

Mechanisms of viral drug resistance towards acyclovir, famciclovir, ganciclovir? Any drug good against drug resistance virus?

Answer 11

Mutated viral thymidine kinase
Foscarnet, Cidofovir
Viral DNA polymerase inhibitor

Question 12

Penicillin which is good against pseudomonas

Answer 12

piperacillin, ticarcillin

Question 13

Adverse effects of cephalosporins (5)

Answer 13

Hypersensitivity, AIHA, disulfiram-like rxn, Vit K deficiency. Aminoglycosides nephrotoxicity

Question 14

Which cephalosporins can cross BBB?

Answer 14

3rd gen

Question 15

B-lactamase inhibitors (4)

Answer 15

clavulanic acid, avibactam, sulbactam , tazobactam

Question 16

Drug to reduce inactivation of carbapenem. MOA?

Answer 16

cilastatin, blocks renal dehydropeptidase 1

Question 17

Adverse effects of carbapenem (2)

Answer 17

Rash, CNS toxicity (seizure) at high plasma lvl

Question 18

Adverse effects of vancomycins (5)

Answer 18

vancomycin is great but NOT trouble Free
NOT F
Nephrotoxicity, Ototoxicity, Thrombophlebitis, Flushing (red man syndrome), DRESS syndrome

Question 19

vancomycin:
1. MOA
2. Mechanism of resistance

Answer 19

1. Bind to D-Ala-D-Ala to prevent cell wall peptidoglycan formation
2. D-Ala-D-ala amino acid modification of bacteria

Question 20

aminoglycoside: (name few)
1. MOA
2. Mechanism of resistance

Answer 20

amikacin, gentamycin, tobramcin, neomycin, streptomycin (b-ANGS-a-T) (Amin is a Bangsat who caNNOT kill anaerobes)

1. inhibit initiation complex by bind to 30S ribosome (buy AT 30, CCEL at 50)
2. deactivated by bacterial transferase enzymes

Question 21

Aminoglycoside (name few): adverse effects

Answer 21

amikacin, gentamycin, tobramcin, neomycin, streptomycin (b-ANGS-a-T) (Amin is a Bangsat who caNNOT kill anaerobes)
NNOT
Nephrotoxicity, Neuromuscular blockade, Ototoxicity, Teratogenicity

Question 22

Tetracyclines:

1. MOA
2. Mechanism of resistance

Answer 22

1. prevent attachment of aminoacyl-tRNA by bind to 30S ribosome (buy AT 30, CCEL at 50)
2. plasmid-encoded transport pump

Question 23

Tetracyclines: adverse effects (4)

Answer 23

teeth yellowing, inhibit bone growth in children, teratogenic, photosensitivity

Question 24

Chloramphenicol:

1. MOA
2. Mechanism of resistance
3. Common areas of usage

Answer 24

1. blocks peptidytransferase by bind to 50S ribosome (buy AT 30, CCEL at 50)
2. deactivated by plasmid-encoded acetyltransferase
3. Common meningitis, rickettsia disease

Question 25

Chloramphenicol: adverse effects (3)

Answer 25

anemia (dose dependent), aplastic anemia (dose independent), gray baby syndrome (baby lack UDP-glucuronosyltransferase)

Question 26

Clindamycin: MOA

Answer 26

1. Blocks peptide translocation at 50S ribosome

Question 27

Clindamycin: adverse effect

Answer 27

Pseudomembranous colliitis

Question 28

Macrolides (name few): 1. MOA 2. Mechanism of resistance

Answer 28

MACE (azithromycin, clarithromycin, erythromycin) 1. Blocks peptide translocation at 23S rRNA of 50S ribosome 2. Prevents drug binding by methylation of 23S rRNA binding site

Question 29

Macrolides: adverse effect

Answer 29

MACROlides | gi Motility issue, Arrthymia by prolonged QT, Cholestatic hepatitis, Rash, eOsinophilia

Question 30

Linezolid 1. MOA 2. Mechanism of resistance 3. Common areas of usage

Answer 30

1. Prevent formation of initiation complex by binding to 50S ribosome 2. Point mutation of ribosome RNA 3. VRE, MRSA

Question 31

Linezolid: adverse effect （3）

Answer 31

Bone marrow suppression, peripheral neuropathy, serotonin syndrome

Question 32

Sulfonamides 1. MOA 2. Mechanism of resistance

Answer 32

1. inhibits dihydropteroate synthase (folate synthesis) | 2. altered bacterial dihydropteroate synthase enzyme, bacterial decrease uptake or increase PABA synthesis

Question 33

Sulfonamides: adverse effect （6）

Answer 33

hypersensitivity, hemolysis (G6PD Def), nephrotoxicity (tubulointerstitial nephritis), photosensitivity, SJS, Kernicterus (infants), displace other drugs from albumin (warfarin)

Question 34

Trimethoprim: MOA

Answer 34

1. inhibits dihydrofolate reductase (DHFR)

Question 35

Trimethoprim: adverse effect (4)

Answer 35

hyperkalemia, megaloblastic anemia, leukopenia, granulocytopenia (avoided with leucovorin/folinic acid)

Question 36

Dapsone: 1. MOA 2. adverse effect (3) 3. Common areas of usage

Answer 36

1. same with sulfonamides = inhibits dihydropteroate synthase (folate synthesis) 2. hemolysis (G6PD Def), methemoglobulinemia, agranulocytosis 3. Leprosy (lepromatous, tuberculoid)

Question 37

Fluoroquinolones: (name few) 1. MOA 2. Adverse effects (3)

Answer 37

Ciprofloxacin 1. inhibits topoisomerase 2 (DNA gyrase), topoisomerase 4 2. chromosome-encoded mutation in DNA gyrase, efflux pump, plasmid-mediated resistance

Question 38

``` Fluoroquinolones: (name few) adverse effect(5) ```

Answer 38

GI disturbance, skin rash, tendonitis/tendon rupture, myalgia, cartilage damage

Question 39

Metronidazole: MOA

Answer 39

Form toxic free radical

Question 40

Metronidazole: adverse effect (2)

Answer 40

Disulfiram-like rxn, metallic taste

Question 41

Echinocandins: 1. Name few 2. Common areas of usage 3. MOA 4. Adverse effects (1)

Answer 41

Echinocandins: 1. Caspofungin, -fungins 2. To treat candida and aspergillus infection ONLY 3. inhibits beta-1,3-D glycan component of cell wall 4. Flushing

Question 42

Rifamycin 1. MOA 2. Mechanisms of resistance 3. Adverse effects

Answer 42

1. Inhibits DNA dependent RNA polymerase 2. reduce binding of drug to RNA polymerase 3. orange body fluids * P450 inducer, high risk of resistance if used alone

Question 43

Isoniazid 1. MOA and key requirement for activation 2. Mechanisms of resistance 3. Adverse effects (2)

Answer 43

1. reduce synthesis of mycolic acid. depedent on bacterial catalase peroxidase (encoded by KatG) 2. underexpression of KatG 3. drug induced SLE, Vit B6 deficiency (peripheral neruopathy, sideroblastic anemia) * the ONLY ONE can be used as monotherapy

Question 44

Pyrazinamide 1. MOA 2. Adverse effects

Answer 44

1. dont know | 2. Hyperuricemia, hepatotoxicity

Question 45

Ethambutol 1. MOA 2. Adverse effects

Answer 45

1. block arabinosyltransferase to reduce carbohydrate polymerization of cell wall 2. optic neuropathy

Question 46

List down medications to treat Hep C. 1. their MOA 2. important side effects

Answer 46

Rainbow 5 Ribavirin, NS5A inhib., NS5B inhib., NS3/4A inhib. NS5A = -asvir NS5B = -buvir NS3/4A come before that = -previr Simeprevir = photosensitivity, rash Ribavirin (adjunct) = hemolytic anemia, teratogen

Question 47

List down some NRTI 1. MOA 2. Adverse effects (4)

Answer 47

Emtricitabine, Lamivudine, Tenofovir, Zidovudine 1. Inhibits nucleotide binding to reverse transcriptase 2. Bone marrow suppression, peripheral neuropathy, lactic acidosis, anemia (ZDV)

Question 48

List down some NNRTI 1. MOA 2. Adverse effects (4)

Answer 48

Efavirenz, Nevirapine, Delavirdine 1. Inhibits reverse transcriptase via other pathway than NRTIs 2. Rash, hepatotoxic, vivid dream, CNS symptoms

Question 49

List down some integrase inhibitors 1. MOA 2. Adverse effects (1)

Answer 49

- tegravir 1. Prevents integration of HIV into host cell 2. raised CK

Question 50

List down some Protease inhibitors 1. MOA 2. Adverse effects (3)

Answer 50

- navir 1. Prevents maturation of HIV by blocking HIV-1 protease 2. Hyperglycemia, lipodytrophy, GI disturbance