Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Pharmacology > Antimicrobial drugs > Flashcards

Antimicrobial drugs Flashcards

(80 cards)

Start Studying
1
Q

Penicillin

A

Class: beta-lactam
Bacteriocidal, beta lactamase sensitive

Penicillin G (IV, IM) Penicillin V (oral)

Uses: Gram (+), gram(-) cocci and spirochetes

Mechanism: binds PBP (penicillin binding protein) to disrupt cell wall, blocks transpeptidase -> inhibits formation of peptidoglycan cross linking in cell wall-> abnormal cell wall structure –> cell death; activates autolytic enzymes –> cell death

Side effects: Hypersensitivity rxns- rashes, itchy eyes, swollen tongue or face, some can have anaphylaxis; High penicillin doses -> autoimmune hemolytic anemia (Abs against complex of penicillin attached to RBC -> complement activation-> removal by spleen)

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

Antipseudomonal penicillins (carboxypenicillins)

A

Beta lactam antibiotic, Bacteriocidal, beta lactamase sensitive

Ex: Ticarcillin, Carbenicillin, Piperacillin

Uses: extended spectrum - cover gram (-) bacteria: pseudomonas and proteus

Same mechanism as penicillin- bind PBP, blocks transpeptidase, activates autolytic enzymes

Use w clavulanic acid (beta lactamase inhibitor)

Hypersensitivity reactions - same as penicillin

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

Ticarcillin

A

Antipseudomonal penicillin, used with clavulanic acid= Timentin
injectable

Used for pseudomonal infections

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

Carbenicillin

A

beta lactam, used for pseudomonal infections, limited gram + coverage

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

Piperacillin

A

beta lactam used for pseudomonal infections - combined with beta lactamase inhibitor-> piperacillin tazobactam combo
Cannot be given orally -> give as IV or IM injection

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

Aminopenicillin uses

A

beta lactam antibiotics, same mechanism as penicillin

Combine with clavulanic acid (beta lactamase inhibitor)

Hypersensitivity rxn like with penicillin

Ex: Ampicillin, Amoxicillin

Treat most gram (+) infections and some gram (-) infectsion such as: H. influenzae, E. coli, Enterococci, Listeria, Proteus, Salmonella, Shigella

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

Ampicillin

A

aminopenicillin, gram (+) and limited gram (-)

can cause rash if mistakenly used with patients with mononucleosis

associated with pseudomembranous colitis precipitation from C. diff after ampicillin

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

Amoxicillin

A

aminopenicillin, used for otitis media, skin infections, strep throat

usually combined with bet lactamase inhibitor (clavulanic acid) and given orally

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

Clavulanic acid

A

beta lactamase inhibitor - binds to active site,

added to penicillin antibiotics:
Augmentin= amoxicillin + clavulanic acid
Timentin= ticarcillin + clavulanic acid

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

Sulbactam

A

beta lactamase inhibitor, commonly used with cefoperazone or ampicillin

Administered via injection

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

Tazobactam

A

beta lactamase inhibitor,
usually combined with extended spectrum antipseudomonal antibiotics:
piperacillin + tazobactam = Tazocin

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

Cephalosporin - general characteristics

A

beta lactam drug, inhibits cell wall synthesis

higher resistance to beta lactamases –> more effective and cover more infections

Bactericidal

Side effects:

  • Hypersensitivity rxn (penicillin hypersensitivity cross reacts w cephalosporins)
  • Vitamin K deficiency with long term use
  • Increased nephrotoxicity when used with aminoglycosides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

1st gen cephalosporins

A

beta lactam drug

Ex: cefazolin (given IM or IV for gram+ skin infections, frequently used pre-op prevent s. aureus), cephalexin (given orally, commonly used to treat gram + infections in middle ear, bone, lungs, skin and endocarditis prophylaxis)

Treats: Gram+ cocci, Proteus, E. coli, Klebsiella,

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

2nd gen cephalosporins

A

beta lactam drug, slightly more extensive than 1st gen

Ex: cefoxitin, cefuroxime, cefaclor

Uses: Gram+ cocci, Proteus, E.coli, Klebsiella, H. influenzae, Neisseria, Serratia, Enterobacter

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

Cefoxitin

A

2nd generation cephalosporin
Strong beta-lactamase inhibitor
Used for gram-, gram+ and anaerobes

Not effective against pseudomonas and enterococci

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

Cefaclor

A

2nd gen cephalosporin

Used for gram + and - bacteria

Treats septicemia, pneumonia peritonitis, UTI and biliary tract infections

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

Cefuroxime

A

2nd gen cephalosporin

can cross BBB

Active against H. influenzae, N. gonorrhea, lyme disease (borrelia)

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

Cefotaxime

A

3rd gen cephalosporin, Can cross BBB

Treat respiratory tract, connective tissue, UTI, genital, meninges, blood infections

Covers most gram(-) EXCEPT psuedomonas
gram(+) EXCEPT enterococcus

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

Ceftriaxone

A

3rd gen cephalosporin, Can cross BBB

Used for community acquired pneumonia, H. influenzae, bacterial meningitis, disseminated lyme disease

*IM injection can be given for gonorrhea

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

Ceftazidime

A

3rd gen cephalosporin

treats gram+ and gram- AND psuedomonas! (unlike other 3rd gen drugs)

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

3rd generation cephalosporins

A

used to combat serious gram (-) infections that are resistant to other beta lactams

Cefotaxime, ceftriaxone, ceftazidime

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

4th generation cephalosporins

A

beta lactam antibiotic

most extensive coverage for gram (+) and (-) AND PSEUDOMONAS, and Staph aureus

Ex: cefepime

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

Cefepime

A

4th gen cephalosporin

used for moderate-severe hospital acquired infections by pseudomonas and can cover resistant Strep. pneumonia and enterobacteriaceae

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

5th generation cephalosporins

A

beta lactam
broad spectrum gram (+) and (-), target resistant organisms like MRSA, does NOT cover pseudomonas

Ex: ceftobiprole, ceftaroline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Ceftobiprole
5th gen cephalosporin strong antipseudomonal activity and activity against MRSA, strep pneumonia, enterococci
26
Ceftaroline
5th gen cephalosporin broad spectrum against gram (+) MRSA, MRSE, VRE Does NOT have good coverage of gram (-) bacteria like bacteroides (gram - anaerobes)
27
Vancomycin - mechanism and use
glycopeptide antibiotic, bactericidal Used to treat serious infections by gram (+) ONLY susceptible organisms: MRSA, C. diff (given orally when unresponsive to metronidazole), Enterococci resistant to penicillin derivatives Mechanism: forms H-bonds w D-Ala-D-Ala moities of cell wall -> prevents synthesis of polymers N-acetylmuramic acid and N-acetylclucosamine (forms backbone strands of cell wall), also prevents polymer cross linking Resistance mechanism: D-Ala-D-Ala changes to D-Ala-D-Lac
28
Vancomycin - toxicity
Thrombophlebitis - swelling and inflammation of veins caused by blood clot, complication of IV vancomycin Nephrotoxicity, Ototoxicity Diffuse flushing - "red man syndrome" w/in 10 minutes of infusion - erythematous rash of face, neck and torso due to mast cell degranulation; can be prevented with slow infusion and antihistamines
29
Imipenem
Carbapenem, beta lactamase resistant antibiotic, inhibits cell wall synthesis Uses: broad spectrum gram+, gram-, aerobes and anaerobes * *Susceptible to degradation by renal dehydropeptidase I in renal tubules - -> Must be co-administered with cilastatin (inhibits renal dehydropeptidase I) **seizure risk!
30
Meropenem
Carbapenem, beta lactamase resistant antibiotic, inhibits cell wall synthesis Uses: broad spectrum gram+, gram-, aerobes and anaerobes * reduced seizure risk, less CNS toxicity risk * NOT degredated by dehydropeptidase I
31
Carbapenem toxicities
GI distress (nausea, diarrhea), skin rash, seizures (imipenem>meropenem),
32
Aztreonam
monobactam, more resistant to beta lactamases (may be inactivated by some extended spectrum) mechanism: binds PBP3 (low affinity to PBP of gram (+) and anaerobes) and inhibits bacterial cell wall synthesis -> bactericidal Uses: For patients w penicillin allergy and those w renal insufficiency who cant tolerate aminoglycosides. Works against gram (-) aerobes, especially bacilli: Pseudomonas, Enterobacter, E. coli, Haemophilus, Klebsiella, Proteus Doesn't work against gram (+) or anaerobic bacteria Can be used synergistically with aminoglycosides, especially for psuedomonas *Does NOT cause penicillin allergy
33
Which drugs are 30S protein synthesis inhibitors?
Aminoglycosides and tetracyclines
34
Which drugs are 50S protein synthesis inhibitors?
Chloramphenicol, clindamycin, erythromycin, lincomycin, linezolid
35
Aminoglycosides
Protein synthesis inhibitors - bind to 30S subunit to inhibit formation of initiation complex -> misreading mRNA -> bacteriacidal Ex: Gentamicin, Neomycin, Amikacin, Tobramycin Use: severe gram (-) rod infections, synergistic with beta-lactam antibiotics, *Neomycin for bowel surgery Require O2 for uptake-> ineffective against anaerobes Toxicities: Nephrotoxicity, Neuromuscular blockade, Ototoxicity (especially w loop diuretics), Teratogen Resistance mechanism: inactivation of drug by bacterial transferase enzymes
36
Tetracyclines
Protein synthesis inhibitors - bind to 30S subunit and prevent attachment of aminoacyl-tRNA, *bacteriostatic *tetracycline chelates divalent cations (Ca2, Mg2, Fe2) and inhibit its absorption -> do NOT take with milk, antacids or iron! Examples: doxycyline, demeclocycline, minocycline Clinical use: Lyme disease (borrelia), H. pylori, M. pneumonia, Rickettsia and Chlamydia Toxicities: GI distress, photosensitivity, contraindicated in pregnancy- teratogen, discoloration of teeth and inhibition of bone growth in children.
37
Chloramphenicol
Protein synthesis inhibitors - inhibits 50S peptidyltransferase (can't form peptide bonds btwn adjacent AAs), bacteriostatic Associated with bone marrow toxicity: anemia (dose dependent), aplastic anemia (dose independent), gray baby syndrome --> used conservatively in US for meningitis More widely used in developing countries bc cheap
38
Clindamycin
Protein synthesis inhibitors - binds 50S subunit and inhibits ribosomal translocation (prevents elongation of polypeptide chain) similar mechanism to macrolides. Bacteriostatic Used for anaerobic infections- bacteroides fragilis and C. perfringens (above diaphragm vs metronidazole below diaphragm)- aspiration pneumonia, lung abscess, Toxicity: pseudomembranous colitis (C.diff), fever, diarrhea
39
Erythromycin
Macrolide, inhibits protein synthesis by binding 23S rRNA of 50S subunit -> blocks translocation Uses: atypical pneumonia by Mycoplasma, Chlamydia and Legionella, URIs and STDs Toxicity: *motilin agonist -> GI disturbances *P450 inhibitor -> avoid use with statins (causes myopathy) and can increase serum concentrations of anticoagulants and theophyllines (respiratory disease med)
40
Lincomycin
Similar in structure to macrolide, protein synthesis inhibitor- inhibits 50S *high toxicity -> rarely used unless patient with penicillin allergy and bacteria highly resistant
41
Linezolid
Drug class: oxazolidinones Mech: protein synthesis inhibitor- inhibits 50S from forming initiation complex Uses: gram (+) infections resistant to other antibiotics- MRSA, VRE, Strep Indications: infection of skin, soft tissues, and hospital acquired pneumonia Toxicity: bone marrow suppression-> thrombocytopenia, peripheral neuropathy, serotonin syndrome
42
Dicloxacillin, nacillin, oxacillin
penicillinase-resistant penicillins same mechanism as penicillin -> large R group blocks access of beta lactamase *use nafcillin for staph aureus (except MRSA) Toxicity: hypersensitivity rxn, interstitial nephritis
43
Doxycycline
Tetracycline drug Used in prophylaxis for malaria *unique: fecally eliminated! --> can use in patients with renal failure
44
Demeclocyline
tetracycline used in treatment of SIADH, since it is an ADH antagonist *In patients without SIADH, it can induce nephrogenic diabetes insipidus
45
Minocycline
tetracycline with broader spectrum than rest of group * long acting- t1/2 2-4x longer * highest action in brain and prostate - > greatest CNS side effects like vertigo
46
Macrolides
Protein synthesis inhibitor Examples: Azithromycin, clarithromycin (also used in H. pylori triple therapy), erythromycin Mechanism: Blocks translocation "macroslides", binds to 23S rRNA of 50S, bacteriostatic Use: Gram(+) cocci (strep infections w penicillin allergies), Atypical pneumonias, STIs (Chlamydia), B. pertussis, Toxicity: GI Motility issues (diarrhea), Arrhythmia caused by prolonged QT, Cholestatic hepatitis, Rash, Eosinophilia *Clarithromycin and erthromycin inhibit cytochrome p450 -> increase serum concentration of anticoagulants and theophyllines, *Avoid using with statins -> myopathy Resistance: methylation of 23S rRNA binding site
47
Trimethoprim
Mech: Bacterial dihydrofolate reductase inhibitor-> cant make THF, Bacteriostatic Clinical use: used in combo with sulfonamides (trimethoprim-sulfamethoxazole, TMP-SMX) -> sequential block of folate synthesis --> UTIs, Shigella, Salmonella, Pneumocystis jirovecii pneumonia treatment and prophylaxis, toxoplasmosis prophylaxis Toxicity: "TMP Treats Marrow Poorly" Megaloblastic anemia, leukopenia, granulocytopenia - supplement with folinic acid (aka Leucovorin)
48
Sulfonamides
Ex: Sulfamethoxazole (SMX, used with trimethoprim against staph, strep, e.coli and oral anaerobes), sulfisoxazole, sulfadiazine (used in combo with pyrimethamine to treat toxoplasmosis) Mech: PABA competitive antagonist, inhibits dihydropteroate synthase -> inhibits folate synthesis Bacteriostatic, but bactericidal when combined with TMP Clinical use: gram (+) and (-), Nocardia, Chlamydia Toxicity: ~3% will have adverse rxns -> hypersensitivity rxn, hemolysis if G6PD deficient, nephrotoxicity (acetylated drug is insoluble in acidic urine and precipitates into crystals, prevent by hydration and alkalinization of urine), photosensitivity, displace drugs from albumin (warfrin), Kernicterus in infants (bilirubin accumulates in gray matter bc sulfonamides displaces from albumin)
49
Fluoroquinolones - examples, mechanism and clinical use
"-floxacin" Ex: Ciprofloxacin, norfloxacin, levofloxacin, moxifloxacin (use limited to serious life threatening infections when other drugs cant be used) Mechanism: Inhibits prokaryotic topoisomerase II (DNA gyrase) and topoisomerase IV Bactericidal Uses: gram (-) rods or urinary and GI tracts- incl psuedomonas and neisseria, some gram (+)
50
Ciprofloxacin
Fluoroquinolone Uses: Strong activity against gram (-) rods like E. coli, 1st line for UTIs P450 inhibitor
51
Fluoroquinolone toxicity
GI upset, superinfections, skin rashes, headache, dizziness Less common: leg cramps and myalgias (especially in kids) Contraindicated in pregnancy- Teratogen, nursing women and children cartilage damage Tendonitis or achilles tendon rupture in elderly and patients taking prednisone
52
Daptomycin
Lipopeptide disrupts cell membrane of gram (+) cocci Clinical use: MRSA, bacteremia, endocarditis, VRE *NOT used for pneumonia Toxicity: myopathy rhabdomyolysis
53
Metronidazole
Mechanism: forms toxic free radical metabolites in cell -> Bactericidal and antiprotozoal Clinical use: Giardia, Entamoeba, Trichomonas, Gardnerella vaginalis, Anaerobes (bacteroides, c. diff) BELOW diaphragm (contrast w clindamycin), Used with PPI and clarithromycin for triple therapy for H. pylori Toxicity: disulfram-like rxn w/ alcohol (flushing, tachycardia, hypotension), HA, metallic taste
54
What drugs are used for M. tuberculosis prophylaxis and treatment?
Prophylaxis: Isoniazid Treatment: Rifampin, Isoniazid, Pyrazinamide, Ethambutol
55
What drugs are used for M. avium-intracellulare prophylaxis and treatment?
Prophylaxis: Azithromycin, rifabutin Treatment: Azithromycin or clarithromycin + ethambutol. Can add rifabutin or cipro
56
What drugs are used to treat M. leprae?
Tuberculoid form: dapsone and rifampin | Lepromatous form: dapson, rifampin and clofazimine
57
Rifamycins
Rifampin, rifabutin Mechanism: Inhibit DNA-dependent RNA polymerase -> blocks RNA polymerization Clinical use: M. tuberculosis; delay resistance to dapsone for leprosy. Prophylaxis for meningococcal infection and prophylaxis in contacts of kids w H. influenzae type B Toxicity: Orange body fluids (nontoxic), hepatotoxicity and drug interactions (induce P450) *Rifabutin favored over rifamin in HIV patients, less P450 stimulation* Resistance: monotherapy rapidly leads to resistance, mutations reduce drug binding to RNA polymerase
58
Isoniazid
Mechamism: decrease synthesis of mycolic acid, Note: bacterial catalase-peroxidase (KatG) needed to convert INH to active metabolite Clinical use: TB, prophylaxis against TB *Different INH half lifes in slow/fast acetylators Toxicity: Can cause B6 deficiency, Neurotoxicity (can be prevented by B6), hepatotoxicity, drug induced lupus. Resistance: mutations in KatG (decreased bacterial catalase-peroxidase)
59
Which drugs are associated with drug-induced SLE?
Isoniazid (TB treatment), hydralazine (vasodilator for HTN), procainamide (anti arrhythmic)
60
Pyrazinamide
Used to treat TB Toxicity: hyperuricemia (gout), hepatotoxicity
61
Ethambutol
mechanism: Blocks arabinosyl transferase-> decreases carbohydrate polymerization of mycobacterium cell wall Use: TB treatment Toxicity: Optic neuropathy (red-green color blindness)
62
High risk for endocarditis and undergoing surgical/dental procedure - what drug to use?
Amoxicillin
63
Exposure to gonorrhea - what drug to use?
Ceftriaxone
64
Hx of recurrent UTIs - what drug to use?
TMP-SMX
65
Exposure to meningococcal infection - what drug to use?
Ceftriaxone, ciprofloxacin, or rifampin
66
Pregnant woman carrying group B strep - what drug to use?
Penicillin G
67
Prevention of gonococcal conjunctivitis in newborn - what drug to use?
Erythromycin ointment
68
Prevent postsurgical infection from S. aureus
Cefazolin
69
Prophylaxis of strep pharyngitis in child with prior rheumatic fever - what drug?
benzathine penicillin G or oral penicillin V
70
exposure to syphilis - what drug to give?
Benzathine penicillin G
71
Prophylaxis in HIV patient CD4
TMP-SMX, prevent pneumocystis pneumonia
72
Prophylaxis in HIV patient CD4
TMP-SMX, prevent pneumocystis pneumonia and toxoplasmosis
73
Prophylaxis in HIV patient CD4
azithromycin or clarithromycin, prevent mycobacterium avium complex
74
Treatment of MRSA
Vancomycin, daptomycin, linezolid, tigecycline, ceftaroline (5th gen cephalosporin)
75
Treatment of VRE
linezolid and streptogramins (quinupristin, dalfopristin)
76
Treatment of multi-drug resistant pseudomonas and acinetobacter baumannii
polymyxins B and E
77
Polymyxins
Cationic- bind to cell membranes by interacting w phospholipids, alter structure -> permeable to water -> cell death Uses: resistant gram (-) infections: multidrug resistant psuedomonas or highly resistant enterobacteriaceae, last resort! Toxicity: Neurotoxicity and Renal Tubular Necrosis
78
Treatment of C. diff
Oral metronidazole (mild to moderate), oral vancomycin (severe), Fidaxomycin for recurrent C.diff (bacteriacidal with less effect on normal flora than metronidazole or vancomycin)
79
What drugs are commonly used to treat MRSA? What are the common side effects of each?
Vancomycin - red man syndrome Daptomycin - myopathy, rhabdomyolysis (increased CPK) Linezolid - bone marrow suppression, peripheral neuropathy, serotonin syndrome
80
Antibiotics effective against Psuedomonas
Class/ Drugs Anti-pseudomonal penicillins: Ticarcillin, Piperacillin Cephalosoprins: Ceftazidime (3rd gen), Cefepime (4th gen) Aminoglycosides: Amikacin, Gentamicin, Tobramycin Fluoroquinolones: Cipro, Levofloxacin Monobactams: aztreonam Carbapenems: imipenem, meropenem

Pharmacology (19 decks)

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