Antimicrobials Flashcards
- Which condition do you use Amphotericin B? Amphotericin B MOA?
- When would you add an antifungal adjuvant? The antifungal adjuvant MOA?
- Severe systemic mycotic infection. (binds ergosterol to allow leakage)
- Cryptococcal meningitis add flucytosine (blocks conversion of 5-FU by cytosine deaminase)
Adverse effects of using Amphotericin B
AAmPHotericiN
Anemia, **Arrhythmia, Makes u feverish, **Phlebitis, Hypotension, -oterici Nephrotoxicity B
Which condition do you use nystatin? MOA?
Oral candidiasis, vaginal/pelvic candidiasis. (binds ergosterol to allow leakage)
Which condition do you use Azoles? MOA? Key adverse effects?
Most local, less serious systemic infection. (inhibit 14-a-demethylase that forms ergosterol from lanosterol)
MOA: gynecomastia (esp ketoconazole)
Which condition do you use terbinafine? MOA?
Dermatophytoses (inhibits Squalene epoxide to form lanosterol from squalene) (strong TERBIN good against SQUAL)
Which condition do you use Griseofluvin? MOA? Key complications?
oral treatment for severe superficial infections, dermatophytes. (MOA: interferes with microtubule a/b-tubulin dimer)
A/E: teratogenic,carcinogenic, CNS symptoms, **disulfiram-like rxn
What do you use to treat influenza? Which mechanisms does it prevent? What is the point of consideration while prescribing this drug?
Zanamivir, oseltamivir
MOA: inhibit influenza neuraminidase to prevent release of progeny virus.
Use the drug within 48 hr of sx
When do we decide to use acyclovir, famciclovir, ganciclovir?
Acyclovir: VZV, HSV
famciclovir: VZV
ganciclovir: CMV
A/E of acyclovir and famciclovir. Difference between the MOA of both
crystal uropathy.
Both inhibits viral DNA polymerase.
Acyclovir via chain termination, famciclovir via act as competitive inhibitor for viral dGTP
A/E of ganciclovir
bone marrow suppression, nephrotoxicity
Mechanisms of viral drug resistance towards acyclovir, famciclovir, ganciclovir? Any drug good against drug resistance virus?
Mutated viral thymidine kinase
Foscarnet, Cidofovir
Viral DNA polymerase inhibitor
Penicillin which is good against pseudomonas
piperacillin, ticarcillin
Adverse effects of cephalosporins (5)
Hypersensitivity, AIHA, disulfiram-like rxn, Vit K deficiency. Aminoglycosides nephrotoxicity
Which cephalosporins can cross BBB?
3rd gen
B-lactamase inhibitors (4)
clavulanic acid, avibactam, sulbactam , tazobactam
Drug to reduce inactivation of carbapenem. MOA?
cilastatin, blocks renal dehydropeptidase 1
Adverse effects of carbapenem (2)
Rash, CNS toxicity (seizure) at high plasma lvl
Adverse effects of vancomycins (5)
vancomycin is great but NOT trouble Free
NOT F
Nephrotoxicity, Ototoxicity, Thrombophlebitis, Flushing (red man syndrome), DRESS syndrome
vancomycin:
1. MOA
2. Mechanism of resistance
- Bind to D-Ala-D-Ala to prevent cell wall peptidoglycan formation
- D-Ala-D-ala amino acid modification of bacteria
aminoglycoside: (name few)
1. MOA
2. Mechanism of resistance
amikacin, gentamycin, tobramcin, neomycin, streptomycin (b-ANGS-a-T) (Amin is a Bangsat who caNNOT kill anaerobes)
- inhibit initiation complex by bind to 30S ribosome (buy AT 30, CCEL at 50)
- deactivated by bacterial transferase enzymes
Aminoglycoside (name few): adverse effects
amikacin, gentamycin, tobramcin, neomycin, streptomycin (b-ANGS-a-T) (Amin is a Bangsat who caNNOT kill anaerobes)
NNOT
Nephrotoxicity, Neuromuscular blockade, Ototoxicity, Teratogenicity
Tetracyclines:
- MOA
- Mechanism of resistance
- prevent attachment of aminoacyl-tRNA by bind to 30S ribosome (buy AT 30, CCEL at 50)
- plasmid-encoded transport pump
Tetracyclines: adverse effects (4)
teeth yellowing, inhibit bone growth in children, teratogenic, photosensitivity
Chloramphenicol:
- MOA
- Mechanism of resistance
- Common areas of usage
- blocks peptidytransferase by bind to 50S ribosome (buy AT 30, CCEL at 50)
- deactivated by plasmid-encoded acetyltransferase
- Common meningitis, rickettsia disease
Chloramphenicol: adverse effects (3)
anemia (dose dependent), aplastic anemia (dose independent), gray baby syndrome (baby lack UDP-glucuronosyltransferase)
Clindamycin: MOA
- Blocks peptide translocation at 50S ribosome
Clindamycin: adverse effect
Pseudomembranous colliitis
Macrolides (name few):
- MOA
- Mechanism of resistance
MACE (azithromycin, clarithromycin, erythromycin)
- Blocks peptide translocation at 23S rRNA of 50S ribosome
- Prevents drug binding by methylation of 23S rRNA binding site
Macrolides: adverse effect
MACROlides
gi Motility issue, Arrthymia by prolonged QT, Cholestatic hepatitis, Rash, eOsinophilia
Linezolid
- MOA
- Mechanism of resistance
- Common areas of usage
- Prevent formation of initiation complex by binding to 50S ribosome
- Point mutation of ribosome RNA
- VRE, MRSA
Linezolid: adverse effect (3)
Bone marrow suppression, peripheral neuropathy, serotonin syndrome
Sulfonamides
- MOA
- Mechanism of resistance
- inhibits dihydropteroate synthase (folate synthesis)
2. altered bacterial dihydropteroate synthase enzyme, bacterial decrease uptake or increase PABA synthesis
Sulfonamides: adverse effect (6)
hypersensitivity, hemolysis (G6PD Def), nephrotoxicity (tubulointerstitial nephritis), photosensitivity, SJS, Kernicterus (infants), displace other drugs from albumin (warfarin)
Trimethoprim: MOA
- inhibits dihydrofolate reductase (DHFR)
Trimethoprim: adverse effect (4)
hyperkalemia, megaloblastic anemia, leukopenia, granulocytopenia (avoided with leucovorin/folinic acid)
Dapsone:
- MOA
- adverse effect (3)
- Common areas of usage
- same with sulfonamides = inhibits dihydropteroate synthase (folate synthesis)
- hemolysis (G6PD Def), methemoglobulinemia, agranulocytosis
- Leprosy (lepromatous, tuberculoid)
Fluoroquinolones: (name few)
- MOA
- Adverse effects (3)
Ciprofloxacin
- inhibits topoisomerase 2 (DNA gyrase), topoisomerase 4
- chromosome-encoded mutation in DNA gyrase, efflux pump, plasmid-mediated resistance
Fluoroquinolones: (name few) adverse effect(5)
GI disturbance, skin rash, tendonitis/tendon rupture, myalgia, cartilage damage
Metronidazole: MOA
Form toxic free radical
Metronidazole: adverse effect (2)
Disulfiram-like rxn, metallic taste
Echinocandins:
- Name few
- Common areas of usage
- MOA
- Adverse effects (1)
Echinocandins:
- Caspofungin, -fungins
- To treat candida and aspergillus infection ONLY
- inhibits beta-1,3-D glycan component of cell wall
- Flushing
Rifamycin
- MOA
- Mechanisms of resistance
- Adverse effects
- Inhibits DNA dependent RNA polymerase
- reduce binding of drug to RNA polymerase
- orange body fluids
* P450 inducer, high risk of resistance if used alone
Isoniazid
- MOA and key requirement for activation
- Mechanisms of resistance
- Adverse effects (2)
- reduce synthesis of mycolic acid. depedent on bacterial catalase peroxidase (encoded by KatG)
- underexpression of KatG
- drug induced SLE, Vit B6 deficiency (peripheral neruopathy, sideroblastic anemia)
* the ONLY ONE can be used as monotherapy
Pyrazinamide
- MOA
- Adverse effects
- dont know
2. Hyperuricemia, hepatotoxicity
Ethambutol
- MOA
- Adverse effects
- block arabinosyltransferase to reduce carbohydrate polymerization of cell wall
- optic neuropathy
List down medications to treat Hep C.
- their MOA
- important side effects
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
List down some NRTI
- MOA
- Adverse effects (4)
Emtricitabine, Lamivudine, Tenofovir, Zidovudine
- Inhibits nucleotide binding to reverse transcriptase
- Bone marrow suppression, peripheral neuropathy, lactic acidosis, anemia (ZDV)
List down some NNRTI
- MOA
- Adverse effects (4)
Efavirenz, Nevirapine, Delavirdine
- Inhibits reverse transcriptase via other pathway than NRTIs
- Rash, hepatotoxic, vivid dream, CNS symptoms
List down some integrase inhibitors
- MOA
- Adverse effects (1)
- tegravir
1. Prevents integration of HIV into host cell
2. raised CK
List down some Protease inhibitors
- MOA
- Adverse effects (3)
- navir
1. Prevents maturation of HIV by blocking HIV-1 protease
2. Hyperglycemia, lipodytrophy, GI disturbance