Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Microbiology > Drugs > Flashcards

Drugs Flashcards

1
Q

Strategies toward development of new antibiotics

A
  1. Combat bacterial resistance mechanisms: develop inhibitors of drug inactivating proteins and efflux transporters, develop drug analogs that are resistant to drug-inactivating proteins
  2. ID new targets for chemotherapy for chemotherapy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Aminoglycosides

A

Antibiotics that inhibit protein synthesis

Includes streptomycin, tobramycin, gentamicin, amikacin, neomycin, kanamycin

Targets 30S ribosomal subunit to irreversibly interfere with protein synthesis by either blocking initiation, blocking ribosomal translocation, or causing mistranslation

Post-antibiotic effect

Bactericidal against many aerobic gram negative bacteria

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

Streptomycin

A

Aminoglycoside

Used as second-line treatment for TB (in combo with other agents to inhibit resistance)

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

Tobramycin

A

Most clinically used aminoglycoside

Used for severe infections caused by aerobic Gram- bacteria that are resistant to other drugs

Often used in combo with beta-lactam antibiotics because synergystic

More expensive than gentamycin

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

Gentamicin

A

Most clinically used aminoglycoside

Used for severe infections caused by aerobic Gram- bacteria that are resistant to other drugs

Often used in combo with beta-lactam antibiotics because synergystic

More cheaper than tobramycin

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

Amikacin

A

Aminoglycosides

Only really used in cases of resistance to tobramycin and gentamicin (there are many bacterially-produced enzymes that cause inactivate tobramycin and genamicin)

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

Neomycin

A

Aminoglycoside

Restricted to topical use only because very toxic (neosporin)

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

Kanamycin

A

Aminoglycoside

Restricted to topical use only because very toxic

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

Adverse Effects from Aminoglycosides

A

Reversible nephrotoxicity

Irreversible ototoxicity (auditory damage and/or vestibular damage)
Auditory damage include tinnitus, high frequency hearing loss
Vestibular damage includes vertigo and ataxia

More likely to occur with use of aminoglycosides longer than 5 days

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

Tetracyclines

A

Inhibit protein synthesis

By blocking 30s ribosomal subunit, inhibit peptide elongation

Bacteriostatic for many aerobic Gram+ and -, including rickettsiae, chlamydiae, and mycoplasmas

Used for rickettsial infections (RMSF, typhus, and Q fever), STIs (chlamydia, urethritis, cervicitis, and epididymititis), respiratory tract infections (pneumonia), Lyme’, anthrax, malaria, and skin/soft tissue infections

Absorption is impaired by food and multivalent cations (Ca2+, Mg2+, Fe2+, and Al3+) cause chelation

Includes tetracycline, oxytetracycline, demeclocycline, minocycline, doxycycline, and tigecycline (first two have VERY short half life)

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

Adverse Effects from Tetracyclines

A

GI problems (nausea, vommitting, diarrhea)

Tooth discoloration and deformity, especially in children

Photosensitization (easily sunburn)

Hepatoxicity during pregnancy

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

Doxycycline

A

Tetracycline used for treatment and prevention of malaria, anthrax, and treatment of Lyme

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

Tigercycline

A

An IV tetracycline with a long half life used for treatment of community acquired pneumonia, intra-abdominal, skin and soft tissue infections cause by MDR bacteria (MRSA, VRE, etc)

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

Macrolides

A

Inhibit protein synthesis

Bind to the 50S subunit to inhibit ribosomal translocation

Bacteriostatic against aerobic Gram+ and some Gram- bacteria

Used for community acquired pneumonia, bronchitis, otitis media, strep throat, chlamydia, diptheria, pertussiss

Erythromycin, carithromycin, azithromycin, and telithromycin

Can cause GI problems and hepatotoxicity

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

Azithromycin

A

Macrolide with long half life

Aka Z-Pak

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

Lincosamide

A

Inhibits protein synthesis

Binds to 50S subunit and interferes with protein synthesis by blocking ribosomal translocation

Bacteriostatic ONLY against aerobic and anaerobic Gram+ bacteria

Used for soft tissue and skin infections

Can cause diarrhea, pseudomembranous colitis caused by C. dif, and skin rash

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

Adverse effects from macrolides

A

Hepatotoxicity-through hypersensitivity reaction

GI Effects-stimulate gut motility-anorexia, nausea, vomiting, and diarrhea accompanying oral administration

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

Strepogramins

A

Protein synthesis inhibitors

Bind to 50S ribosomal subunit to inhibit ribosomal translocation

For VRE and MSSA (not MRSA)

Used against Gram+ bacteria

Quinupristin and dalfopristin

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

Oxazolidinone

A

Protein synthesis inhibitors

Bind to 50S to inhibit initiation step of protein synthesis

Used against aerobic and anaerobic Gram+

Used for treatment of infections caused by MDR gram+ bacteria (MRSA, VRE, and penicillin resistant streptococci)

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

Sulfonamides

A

Inhibit DNA synthesis (anti-folate)

Competitive antagonist of dihydropteroate synthase needed for purine synthesis; act as PABA analogs

Bacteriostatic when used as single agent; bactericidal when used with tripmethoprim (which inhibits DNA synthesis further downstream)

Sulfisoxazole, sulfamethoxazole, and sulfasalazine

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

Sulfisoxazole

A

Sulfonimide (antifolate DNA synthesis inhibitor)

Used for UTIs

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

Sulfamethoxazole

A

Sulfonimide (antifolate DNA synthesis inhibitor)

Used for UTIs

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

Sulfasalazine

A

Sulfonamide (anti-folate DNA synthesis inhibitor)

Used for ulcerative colitis, enteritis, and other IBD
Has anti-inflammatory properties

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

Adverse effects of sulfonamides

A

Hypersensitivity/allergic reactions-fever, rash,

Most serious=crystalluria, hematuria, or obstruction

25
TMP-SMX
Combination of trimethoprim and sulfamethoxazole Both are anti-folates that, when used together, are bactericidal Used for UTIs, pneumonia, Shigellosis, Salmonella, prostatitis, and acute bronchitis Treatment less than 5 days can cause allergic reaction Treatment longer than 5 days can cause megaloblastic anemia and leukopenia
26
Trimethoprim
Inhibits DNA synthesis Blocks DHFR needed to make purines
27
Fluroquinolone
Inhibit DNA synthesis Inhibit DNA gyrase and topoisomerase Bactericidal against Gram- and Gram+ Used for UTIs, diarrhea caused by Shigella or Salmonella or E. Coli, soft tissue and bone and joint infections, intra-abdominal infections, respiratory tract infections Levofloxacin, gemifloxacin, and moxifloxacin effective for respiratory tract infections Cipro used for anthrax (caused by Gram+) Ciprofloxacin, lomefloxacin, levofloxacin, ofloxain, gemifloxacin, moxifloxacin
28
Beta-Lactam Antibiotics
Antibiotic that targets cell wall Inhibit cross linking of peptidoglycan units by mimicking D-Ala-D-Ala to bind to Ser-enzyme Without cell wall, bacteria bursts Combined with beta-lactamase inhibitors 4 types, but all share core ring: penicillin, cephalosporin, monobactam, and carbepenems
29
Beta-lactamase | Action and drug names
Gram- response to beta-lactam antibiotics Clavulanic acid Avibactam-broad spectrum inhibitor Act like transpeptidases, but use water to hydrolyze serine-lactam linkage to irreversibly inactivate beta-lactams and allow for peptidoglycan cross linking Two types: serine and metallo
30
Penicillin | Details and drug names
Beta-lactam antibiotic Use with probenecid to increase half life (prevent excretion) Oral, IV, or IM administration Common: pencillin G Antistaphlycoccal pencillin: oxacillin, cloxacillin, dicloxacillin Extended spectrum: amoxicillin Resistance=MRSA
31
Penicillin G
Beta-lactam antibiotic, Common penicillin Acid labile, beta-lactamase susceptible Gram+, and Gram- cocci
32
Anti-staphylococcal Penicillins
Beta-lactam antibiotic Includes oxacillin, cloxacillin, and dicloxacillin Acid stable, beta-lactamase resistant not suitable for enterococci, anaerobes, and Gram- cocci and rods
33
Amoxicillin
Beta-lactam antibiotic, extended spectrum penicillin Acid stable, beta-lactamase sensitive Greater activity against Gram- because able to penetrate outer membrane With clavulanate=augmentin
34
Cephalosporins
Beta-lactam antibiotic Greater spectrum because increased resistance to beta-lactamases 5 generations
35
Cefazolin
First generation cephalosporin Best for Gram+ Given for surgery prophylaxis
36
Cefamandole
Second generation cephalosporin Gram + and - No allergic cross reactivity with penicillin
37
Ceftazidime
Third generation cephalosporin Extend Gram- at expense of Gram+ Can cross BBB
38
Cefepime
Fourth generation cephalosporin Broad spectrum Penetrates BBB
39
Ceftaroline
Fifth generation cephalosporin Used for MRSA because has high affinity for transpeptidase found in MRSA
40
Monobactams
Beta-lactam antibiotic Active ONLY against Gram-rods Given by IV and excreted rapidly Resistant to beta-lactamases No cross reactivity with pencillin
41
Aztreonam
Beta-lactam antibiotic, Monobactam Only active against Gram- rods
42
Carbapenems
Beta-lactam antibiotic, Imipenem Broad spectrum Cilastatin used to block excretion. Resistant to serine bet-lactamases, but NOT metallo beta-lactamases Cross BBB Cross reactivity with penicillin allergies
43
Imipenem
Beta lactam antibiotic, carbapenem Broad spectrum and can cross BBB
44
Vancomycin
Glycopeptide; Non-beta lactam cell wall inhibitor For Gram+ bacteria, especially staphylococci Too big to affect Gram- Binds tightly to D-Ala-D-Ala to block transglycosylase and transpeptidase action Used for MRSA and methicillin-resistant endocarditis or sepsis Resistance: bacteria switches from D-Ala-D-Ala to D-Ala-D-Lactate, which decreases Vancomycin affinity by 1000x Requires IV administration
45
Dalbavancin
Glycopeptide non-beta lactam antibiotic Derivative of Vancomycin, but only need two doses
46
Oritavancin
Glycopeptide non-beta lactam antibiotic Derivative of Vancomycin, but only need one dose
47
Daptomycin
Lipopeptide non-beta lactam antibiotic Drills pores in inner membrane of Gram+ that allow K+ loss WITHOUT cell rupture
48
Polymyxins
A lipopeptide non-beta lactam antibiotic Binds to a liposaccharide only on outer membrane of GRAM- bacteria and makes perforation leading to permeability of the inner and outer cell membrane Used topically; in neosporin
49
Fosfomycin
Antibiotic inhibitor of peptidoglycan precursors Inhibits MurA, which is needed to catalyze the first committed step (NAG-UDP --> NAM-UDP) Used for Gram+ and- Commonly used for UTIs
50
Bacitracin
Antibiotic inhibitor of peptidoglycan precursors Inhibits dephosphorylation of lipid carrier of peptidoglycan subunits Active only against Gram+ Only used topically
51
D-Cycloserine
Antibiotic inhibitor of peptidoglycan precursors D-Ala analog so inhibits enyzmes needed to convert Ala-->D-Ala (racemase) and glue D-Ala subunits together (D-alanine ligase) Used in combination with other antibiotics as a second line drug to treat TB, but otherwise toxic
52
First line TB drugs
Rifampin Isoniazid Pyrazinamide Ethambutol
53
Features of Second-line TB drugs
Given for MDR-TB Less effective than first line drugs with significant side effects Expensive
54
Isoniazid
First line treatment for TB; targets mycolic acid biosynthesis at FAS-II Bactericidal against both extracellular and intramacrophage mycobacteria Taken orally High probability of resistance, so used with other drugs Pro-drug activated by bacterial enzyme KatG Side effects: hepatitis and peripheral neuropathy (because competitive inhibitor of vitamin B6) Supplement administration with B6 Metabolism varies by genetics; drug inactivated by acetylation
55
Rifampin
First line treatment for TB Inhibits bacterial transcription elongation by inhibiting RNA from interacting with RNApol Bactericidal Administer orally Side effects: flu-like symptoms; increases P450 members including CYP3A which increases elimination of other drugs Harmless red or purple urine
56
Rifabutin | Rifapentine
Derivative of rifampin used as first line treatment for TB Have higher potency, longer half life, and less CYP interference
57
Pyrazinamide
First line treatment for TB that inhibits protein synthesis Bactericidal; pro-drug activated by PZase Oral Inhibits trans-translation so there is a defect in rescue of stalled ribosome and depletion of available ribosomes for protein synthesis Works synergistically with rifampin Rapid emergence of resistance
58
Ethambutol
First line treatment for TB Inhibits incorporation of arabinose in cell wall; cell wall is too weak Oral Side effects: optic neuritis and red green color blindness High probability of resistance

Microbiology (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions