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USMLE Step 1 > Antimicrobial Drugs > Flashcards

Antimicrobial Drugs Flashcards

1
Q

Block cell wall synthesis by inhibition of peptidoglycan cross-linking

A

Penicillin, Methicillin, Ampicillin, Piperacillin, Cephalosporins, Aztreonam, Imipenem

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2
Q

Block peptidoglycan synthesis

A

Bacitracin, Vancomycin

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3
Q

Block nucleotide synthesis by inhibiting folic acid synthesis (involved in methylation)

A

Sulfonamides, trimethopram

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4
Q

Block DNA topoisomerases

A

Fluoroquinolones

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5
Q

Block mRNA synthesis

A

Rifampin

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6
Q

Damage DNA

A

Metronidazole

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7
Q

Block protein synthesis at 50S ribosomal subunit

A

Chloramphenicol, Macrolides, Clindamycin, Streptogramins (Quinupristin, Dalfopristin, Linsezolid)

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8
Q

Block protein synthesis at 30S ribosomal subunit

A

Aminoglycosides, Tetracyclines

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9
Q

Penicillin

A

Penicillin G (IV and IM form), penicillin V (oral), Prototype B-lactam antibiotics

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10
Q

Penicillin Mechanism

A

Bind penicillin-binding proteins (transpeptidases)
Block transpeptidase cross-linking in peptidoglycan
Activate autolytic enzymes

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11
Q

Penicillin Clinical Use

A

Mostly used for gram-positive organisms (S. pneumoniae, S. pyogenes, Actinomyces)
Bacterocidal for gram-positive rods, gram-negative cocci, and spirochetes

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12
Q

Penicillin: Penicillinase resistant?

A

No. Duh!

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13
Q

Penicillin Toxicity

A

Hypersensitivity reactions, Hemolytic anemia

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14
Q

How does penicillin resistance occur?

A

B-lactamases cleave B-lactam ring

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15
Q

Penicillinase resistant penicillins

A

Oxacillin, Nafcillin, Dicloxacillin

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16
Q

Penicillinase resistant penicillins Mechanism

A

Narrow spectrum Bind penicillin-binding proteins (transpeptidases)

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17
Q

How are the “-cillins” penicillinase resistant?

A

Bulky R group blocks access of B-lactamase to B-lactam ring

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18
Q

Penicillinase resistant penicillins Clinical Use

A

S. aureus (except MRSA; resistant because of altered penicillin-binding protein target site)

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19
Q

Penicillinase resistant penicillins Toxicity

A

Hypersensitivity reactions, interstitial nephritis

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20
Q

Aminopenicillins

A

Ampicillin, Amoxicillin

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21
Q

Aminopenicillins: Mechanism

A

Same as penicillin but wider spectrum

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22
Q

Aminopenicillins: Penicillinase resistant or penicillinase sensitive

A

Penicillinase sensitive Also combine with clavulanic acid to protect against B-lactamase

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23
Q

Which has greater oral bioavailability? Amoxicillin or Ampicillin

A

Amoxicillin

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24
Q

Aminopenicillins (Ampicillin, Amoxicillin) : Clinical Use

A

Extended spectrum penicillin - (HELPSS) Haemophilus influenzae, E.coli, Listeria monocytogenes, Proteus mirabilis, Salmonella, Shigella, enterococci

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25
Q

Aminopenicillin (Ampicillin, Amoxicillin) Toxicity

A

Hypersensitivity reactions; ampicillin rash; pseudomembranous colitis

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26
Q

Aminopenicillin (Ampicillin, Amoxicillin) Resistance

A

B-lactamases cleave B-lactam ring

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27
Q

Antipseudomonals

A

Ticarcillin, Piperacillin

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28
Q

Antipseudomonals (Ticarcillin, Piperacillin) Mechanism

A

Same as penicillin Extended spectrum

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29
Q

Ticarcillin, Piperacillin Clinical Use

A

Pseudomonas spp. and gram-negative rods

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30
Q

Ticarcillin, Piperacillin: Penicillinase resistant or Penicillinase sensitive?

A

Penicillinase sensitive Use with clavulanic acid to protect against B-lactamase

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31
Q

B-lactamase inhibitors

A

CAST - Clavulanic Acid Sulbactam, Tazobactum

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32
Q

Cephalosporins: Mechanism

A

B-lactam drugs that inhibit cell wall synthesis but are less susceptible to penicillinases. Bactericidal

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33
Q

Which organisms are not covered by cephalosporins?

A

Organisms typically not covered by cephalosporins are LAME:
Listeria, Atypicals (Chlamydia, Mycoplasma), MRSA, and Enterococci

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34
Q

Which cephalosporin is the exception to the LAME organism rule?

A

Ceftaroline covers MRSA

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35
Q

1st generation cephalosporins

A

Cefazolin, Cephalexin

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36
Q

1st generation cephalosporins coverage

A

1st generation - PEcK
Proteus
E.Coil
Klebsiella

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37
Q

2nd generation cephalosporins

A

Cefoxitin, Cefaclor, Cefuroxime

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38
Q

2nd generation cephalosporin coverage

A 
2nd generation cephalosporins - *HEN PEckS* 
H.influenza
Enterobacter
Neisseria
Proteus
E.Coli
Klebsiella
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39
Q

3rd generation cephalosporins

A

Ceftriaxone, Cefotaxime, Ceftazidime

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40
Q

3rd generation cephalosporins coverage

A

Serious gram-negative infections resistant to other B-lactams

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41
Q

4th generation cephalosporins

A

Cefepime

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42
Q

4th generation cephalosporin coverage

A

Cefepime - increased activity against Pseudomonas and gram-positive organisms

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43
Q

Cephalosporin Toxicity

A

Hypersensitiity reactions, vitamin K deficiency.

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44
Q

Aztreonam: Mechanism

A

A monobactam resistant to B-lactamases. Prevents peptidoglycan cross-linking by binding to PBP3

Synergistic with aminoglycosides. No cross-allergy with penicillins

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45
Q

Aztreonam: Clinical Use

A

Gram-negative rods only - No activity against gram-positives or anaerobes. For penicillin-allergic patients and those with renal insufficiency who cannot tolerate aminoglycosides

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46
Q

Imipenem/Cilastatin, Meropenem: Mechanism

A

Imipenem is a broad-spectrum, B-lactamase-resistant carbapenem. Always administered with cilastatin (inhibitor of renal dehydropeptidase I) to decreased inactivation of drug in renal tubules.

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47
Q

Imipenem/Cilastatin, Meropenem: Clinical Use

A

Gram-positive cocci, gram-negative rods, and anaerobes.

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48
Q

Discuss Meropenem and seizure risk

A

Unlike imipenem/cilastatin, meropenem has reduced risk of seizures, and is stable to dehydropeptidase I

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49
Q

Imipenem/Cilastatin, Meropenem: Toxicity

A

GI distress, skin rash, and CNS toxicity (seizures at high plasma levels)

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50
Q

Vancomycin: Mechanism

A

Inhibits cell wall peptidoglycan formation by binding D-ala D-ala portion of cell wall precursors. Bactericidal

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51
Q

Vancomycin: Clinical Use

A

Gram-positive only - serious, amultidrug-resistant organisms, including MRSA, enterococci, and Clostridium difficile (oral dose for pseudomembranous colitis)

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52
Q

Vancomycin: Toxicity

A 
Well tolerated in general - does *NOT* have many problems
N-ephrotoxicity
O-totoxicity
Tthrombophlebitis
Diffuse flushing
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53
Q

How can one prevent red man syndrome?

A

Red man syndrome - associated w/ vancomycin toxicity.

- mediated by histamine

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54
Q

Vancomycin Resistance

A

Occurs with amino acid change of D-ala D-ala to D-ala D-lac.

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55
Q

Protein synthesis inhibitors target which bacterial ribosome?

A

70S (made up of 50S and 30S subunits), which leave 80S ribosome (human ribosome) unaffected

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56
Q

Aminoglycosides

A

Gentamicin, Neomycin, *Amikacin, Tobramycin, Streptomycin

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57
Q

Macrolide: Clinical Use

A

Atypical pneumonias (Mycoplasma, Chlamydia, Legionella)
STDs (for Chlamydia)
Gram-positive cocci (Streptococcal infections in patients allergic to penicillin

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58
Q

Macrolides: Toxicity

A

MACRO: Motility issues, Arrhythmia caused by prolonged QT, acute Cholestatic hepatitis, Rash, eOsinophilia. Increases serum concentration of theophyllines, oral anticoagulants

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59
Q

Macrolide Resistance

A

Methylation of 23S rRNA binding site

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84
Q

30 S inhibitors

A

“AT” 30
Aminoglycosides
Tetracyclines

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85
Q

50S inhibitors

A

CCEL at 50
Chloramphenicol, Clindamycin
Erythromycin (macrolides)
Linezolid

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86
Q

Aminoglycoside: Mechanism

A

Bacteriocidal

  • bind to 30S ribosomal subunit unit to inhibit formation of initiation complex and cause misreading of mRNA
  • blocks translocation
  • Requires oxygen for uptake thus inaffective against anaerobes
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87
Q

Aminoglycoside: Clinical USe

A

Severe gram-negative rod infections
Syngergistic with B-lactam antibiotics
Neomycin for bowel surgery

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88
Q

Amingoglycoside Toxiciity

A

Nephrotoxicity (esp. when used with cephalosporins)
Neuromusclar blockade
Ototoxicity (esp. when used with loop diuretics - furosemide)
Teratogen

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89
Q

Aminoglycoside resistance

A

Transferase enzymes that inactivate trug by acetylation, phosphorylation or adenylation

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90
Q

Tetracycline

A

Tetracycline, Doxycycline, Demeclocycline

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91
Q

Demeclocycline

A
  • ADH antagonist

- acts as diuretic in SIADH. Rarely used as an antiobiotic

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92
Q

Tetracycline mechanism

A

Bacterostatic:
bind to 30S and prevent attachment of aminoacyl-tRNA
limited CNS prenetration

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93
Q

Contraindications for tetracyclines

A

Don’t use with milk, antacids, or Fe-containing substances because divalent cations inhibit absorption in gut

94
Q

Doxycycline special considerations

A

fecally eliminated

can be used in patients with renal failure

95
Q

Tetracyclines: Clinical Use

A

Borellia borgdoferi
M. pneuominae
- ability to accumulate intracellularly makes it effective against Ricksettia and Chlamydia

96
Q

Tetracycline: Toxicity

A

GI distress
Discoloration of teeth and inhibition of bone growth in children
Photosensitivity
Contraindicated in pregnancy

97
Q

Tetracycline: Resistance

A

Decreased uptake into cells

Increased efflux out of cell by plasmid-encoded transport pumps

98
Q

Macrolides

A

azithromycin, clarithromycin, erythromycin

99
Q

Macrolide: Mechanism

A

Inhibit protein synthesis by blocking translocation;

bind to 23S rRNA of 50 S ribosomal subunit

100
Q

Chloramphenicol

A
  • blocks peptidyltransferase at 50S ribosomal subunit
  • used for Meninigitis (H. influenzae, N. meningitis, S. pneumoniae)
  • not used widely because of toxicity
101
Q

Chloramphenicol: Toxicity

A

anemia (dose dependent)
aplastic (dose INDEPENDENT)
Gray baby syndrome - in premature babies because they lack liver UDP-gluconyl transferase

102
Q

Chloramphenicol: Resistance

A

Plasma-encoded acetyltransferase that inactivates drug

103
Q

Clindamycin

A
  • blocks peptide transfer (transpeptidation) at 50S ribosomal subunit. Bacteriostatic
  • used to treat ANAEROBIC infections in aspiration pneumonia or lung abscesses
  • also treats oral infections with mouth anaerobes
104
Q

Metronidazole vs. Clindamycin

A

Clindamycin - treats anaerobes ABOVE diaphragm

Metronidazole - treats anaerobes BELOW diaphragn

105
Q

Clindamycin: Toxicity

A

Pseudomonas colitis ( C. difficile overgrowth), fever, diarrhea

106
Q

Sulfonadmides:

A

SMX, Sulfisoxiazole, Sulfadiazine

107
Q

Sulfonamide

A

PABA antimetabolit inhibit dihydropteroate synthase. Bacteriostatic

  • treats gram-positive, gram-negative, Nocardia, Chlamydia,
  • Triple sulfas or SMX for simple UTI
108
Q

Sulfonamide: Toxicity

A 
Hypersensitivity reactions
Hemolysis if G6PD deficiency
Nephrotoxicity (tubulointerstitial nephritis)
Photosensitivity
Kernicterus in infants
Displace other drugs from albumin
109
Q

Trimethoprim

A
  • inhibits bacterial dihydrofolate reductase. Bacteriostatic
  • used in combination with sulfonamides (TMP-SMX), causing sequential block of folate synthesis
  • used for UTIs, Shigella, Salmonella, PCP (treatment & prophylaxis)
110
Q

Trimethoprim: Toxicity

A

Megaloblastic anemia, Leukopenia, Granulocytopenia

    • Treat Marrow Poorly
  • May be alleviated with folinic acid (leuvovorin rescue)
111
Q

Fluoroquinolones

A

“-floxacin” , “enoxacin”, nalidixic acid

Ciprofloxain, Norflozacin

112
Q

Fluoroquinolones

A

Inhibit DNA gyrase (topoisomerase II) and topoisomerase IV)

  • Don’t take with antacids
  • use to treat gram-negative rods of urinary and GI tracts (e.g Psuedomonas, Neisseria, gram-positive organisms)
113
Q

Floroquinolones: Toxicity

A

GI upset
Superinfections
Skin rashes
Dizziness
- Can cause tendon rupture (esp. in Achilles tendon) in patients > 60
- Contraindicated in pregnant women and children because may damage cartilate

114
Q

Floroquinolone: Resistance

A

Chromosome-encoded mutation in DNA gyrase
Plasma mediated resistance
Efflux pumps

115
Q

Metronidazole

A
  • forms free radical toxic metabolites in bacterial cell that damages DNA. Bactericdial, Antiprotozoal
  • treats “GET GAP” - Giardia, Entoameoba, Trichomonas Gardnerella vaginalis, Anaerobes
  • Used with proton pump inhibitor and clarithromycin for “triple therapy” for H. pylori
116
Q

Metronidazole: Toxicity

A

Disulfram-like reactiin with alcohol
Headache
Metallic Taste

117
Q

Treatment from M. tuberculosis

A

Prophylaxis: Isoniazid

Treatment: RIPE (Rifampin, Isoniazid, Pyrazinamide, Ethamutol)

118
Q

Treatment for M. avium-intracellulaire

A

Prophylaxis: Azithromycin

Treatment: Azithromycin, Rifampin, Ethambutol, Streptomycin

119
Q

Treatment for M. leprae

A

NO PROPHYLAXIS

Tuberculoid: Dapsone and Rifampin for 6 months
Lepromatous: Dapsone, Rifampin, Clofazimine for 2-5 years

120
Q

Isoniazid:

A
  • inhibits mycolic acid synthesis. Bacterial catalase-peroxidase (KatG) needed to convert INH to active form
  • used for M. tuberculoisis. Only solo prophylaxis for TB
121
Q

Isoniazid Metabolism

A
  • Different INH half lives in fast vs. slow acetylators

- seen in bi-modal plasma concentration graphs

122
Q

Isoniazid: Toxicity

A

Neurotoxicity
Hepatotoxicity
Pyroxidine (VB6) can prevent neurotoxicity, lupus
B6 needed to make NTs (e.g. GABA)

123
Q

Rifampin

A
  • inhibits DNA dependent RNA polymerase
  • treats M. tuberculosis
  • delays resistance to dapsone when leprosy
  • Used for meningococcal prophylaxis and chemoprophylaxis in contacts of children with H. influenzae type b
124
Q

Rifampin: Toxicity

A

minor hepatotoxicity and drug interactions (increase in P-450)
Orange body fluids

125
Q

Pyrazinamide

A
  • uncertain mechanism but may acidify intracellular enviroment by converting to pyrazinoic acid
  • effective in acidic pH of phagolysosomes where TB is engulfed by macrophages are found
  • used to treat TB
126
Q

Pyraniamide: Toxicity

A

Hyperuricemia, Hepatotoxicity

127
Q

Ethambutol

A
  • decreased carbohydrate polymerization of mycobacterium cell wall by blocking arabinosyltransferase
  • treats TB
128
Q

Ethambutol: Toxicity

A

optic neuritis

  • central scotomas
  • decreased visual acuity
  • red-green color blindness
129
Q

Prophylaxis for meningococcal infection

A

Ciprofloxacin (1st line)

Rifampin for children

130
Q

Prophylaxis for Gonorrhea

A

Ceftriazone

131
Q

Syphilis prophylaxis

A

Penicillin G

132
Q

Hx of recurrent UTIs

A

Penicillins

133
Q

Encocarditis with surgical or dental procedures - Prophylaxis

A

Penicillins

134
Q

Pregnant women carrying Group B Strep prophylaxis

A

Intrapartum ampicillin

135
Q

Prophylaxis of strep pharyngitis in child with prior rheumatic fever

A

Oral penicillin

136
Q

Prevention of post surgical infection due to S. aureus

137
Q

Prevention of gonoccocal or chlamydial conjunctivitis in newborn

A

Erythomycin ointment

138
Q

HIV prophylaxis : CD4 < 200 cells/mm3

A

TMP-SMX to prevent PCP pneumonia

139
Q

HIV prophylaxis: CD4 < 100 cells/mm3

A

TMP-SMX to prevent PCP pneumonia and Toxoplasmosis

140
Q

HIV prophylaxis: CD4 < 50 cells/mm3

A

Azithromycin to prevent M. avium complex

141
Q

Treatment of Vancomycin Resistance Enterococci

A

Linezolid

Streptogramins (Quinupristin/Dalfopristin)

142
Q

Amphotericib B

A
  • binds to ergosterols in fungi - forms membrane pores that allow leakage of electrolytes
  • treats systemic mycoses (Cryptococcus, Blastomyces, Coccidioides, Histoplasma, Candida, Mucor
  • Intrathecally for fungal meningitis
  • Supplement K and Mg for altered renal tubule permeability
143
Q

Amphotericin B: Toxicity

A 
Fever/chills ("shake and bake")
Hypotension
Nephrotoxicity
IV phlebitis
Hydration reduces nephrotoxicity
Liposomal amphotericin reduces toxicity
144
Q

Nystatin

A
  • bind to ergosterols
  • can only be used topically
  • used to treat oral candiadis (thrush)
  • topic for diaper rash or vaginal candiadiasis
145
Q

Azoles

A
  • inhibit fungal sterol (ergosterol) synthesis by inhibiting P-450 enzyme that converts lanosterol to ergosterol
  • treats local and less serious mycoses
146
Q

Fluconazole

A

used for chronic suppression of cryptococcal meningitis in AIDS patients and candidal infections of all types

147
Q

Itraconazole

A

treats Blastomycoses, Coccidoides, Histoplasma

148
Q

Clotrimazole and Miconazole

A

treats topical fungal infections

149
Q

Azoles: Toxicity

A

testerone synthesis inhibition - leads to gynecomastia esp. with ketoconazole
- Liver dysfunction (inhibits P-450)

150
Q

Flucytosine:

A
  • inhibits DNA and RNA biosynthesis by conversion to 5-FU by cytoseine deaminase
  • used in systemic fungal infections (esp. in meningitis caused by Cryptococcus) in combination with amphotericin B

TOXICITY:: causes bone marrow suppression

151
Q

Caspofungin, Micafungin

A

inhibits cell wall synthesis by inhibiting synthesis of B-glucan
- treats invasive aspergillosis, Candida

** associated with GI upset, flushing (histamine release)

152
Q

Terbinafine

A
  • inhibits fungal enzyme 2,3 squalene epoxide (thus inhibiting sterol synthesis)
  • used to treat dermatophytes (esp. fungal infections of skin and nails)

** associated with abnormal LFTs, visual disturbances

153
Q

Griseofulvin

A
  • interferes with microtubule function; disrupts mitosis.
  • deposits in keratin containing tissues (e.g. nails)
  • used for oral treatment of superficial infections; inhibits growth of dermatophytes (tinea, ringworm)
154
Q

Griseofulvin: Toxicity

A 
teratogenic
carcinogenic
confusion
headaches
-increase P450 and warfarin metabolism
155
Q

Antiprotozan therapy

A

Pyrimethamine (toxoplasmosis)
Suramin and Melarsoprol (T. cruzei)
Nifuritmox (T. cruzei)
Sodium Stibogluconate (Leischmaniasis)

156
Q

Chloroquine

A
  • blocks detoxification of heme into hemoizin. Heme accumulates and is toxic to plasmodia
  • treats plasmodial species EXCEPT P. falciprum (resistance too high)
    • resistance due to membrane pump that decreases intracellular concentration of drug
  • ** associated with retinopathy
157
Q

Treatment of P. falciprum

A
  • treatment with artemether/lumifantrine

- atovaquone/proguanil

158
Q

Antihelminthic therapy

A

Metrobendole
Pyrantel pamoate
Ivermectin
Diethycarbamazine

159
Q

Zanamivir

A

inhibit influenza neuraminase, decreasing release of progeny virus
- treats and prevents both influenza A and B

160
Q

Ribavirin

A

inhibits synthesis of guanine nucleotide by competively inhibiting IMP dehydrogenase
- used to treat RSV, chronic Hep C

  • ** associated with hemolytic anemia
    • Severe teratogen
161
Q

Acyclovir

A
  • monophosphoryalated by HSV/VZV thymidine kinase
  • Guanosine analog
  • Triphosphate formed by cellular enzymes. Preferentially inhibits viral DNA polymerase by chain termination
162
Q

Acyclovir: Use

A
  • treats HSV and VZV
  • Weak against EBV
  • NO ACTIVITY against CMV
  • Used for mucotaneous and genital lesions and for encephalitis
  • Prophylaxis in immunocompromised patients
  • Valacyclovir, a prodrug has better oral bioavailability
    • Few serous side effects
163
Q

Acyclovir Resistance

A

Mutated viral thymidine kinase

164
Q

Ganciclovir

A

5’-monophophate formed by a CMV viral kinase
Guanosine analong
Triphosphate formed by cellular kinases
Preferentially inhibits viral DNA polymerase
- treats CMV esp in immunocompromised patients
- Valganiclovir - has better oral bioavailability

165
Q

Ganciclovir: Toxicity

A

mutated CMV DNA polymease or lack of viral kinase

166
Q

Foscarnet

A
  • viral DNA polymerase inhibitor that binds to pyrophosphate binding site of enzyme
  • does not require activation by viral enzyme
  • treats CMV retinits in immunocompromised patients when ganciclovir fails
  • treats acyclovir resistant HSV

** associated with nephrotoxicity

167
Q

Forscarnet Resistance

A

mutated DNA polymerase

168
Q

Cidofovir

A

preferentially inhibits viral DNA polymerase. Does not require phosphorylation by viral kinase

  • CMV retinintis in immunocompromised patients
  • acyclovir resistant HSV
  • Long half-ide

*** associated with nephrotoxicity (coadminister with probenecid and IV saline to reduce toxicity

169
Q

HIV therapy

A

HAART - highly active antiretroviral therapy

  • initiated when patients present with AIDS defining illness
  • low CD4 cell counts (< 500 cells/mm3) OR high viral load
  • Regimen consists of 3 drugs to prevent resistance
170
Q

HIV therapy HAART cocktail

A 
TWO NRTIs (nucleoside reverse transcriptase) + 
1 non-nucleoside reverse transcriptase inhibitor OR 1 protease inhibitor OR integrase inhibitor
171
Q

Protease inhibitors (“-inavirs”)

A

Assembly of virions depends on HIV-1 protease which cleaves polypeptide products of HIV mRNA into their functional parts
- Protease inhibitors prevent maturation of new viruses

172
Q

Ritonavir and drug concentrations

A

Ritonavir can book other drug concentrations by inhibiting cytochrome P-450

173
Q

Protease inhibitor (-inavir) Toxicity

A 
Hyperglycemia
GI intolerance (nausea, diarrhea)
Lipodystrophy
Nephropathy
Heamturia (assciated with indinavir)
174
Q

NRTIs (“-vudine”), Emtrictabine, Abacavir, Didanosine

A
  • competitively inhibit nucleotide binding to reverse transcriptase and terminate DNA chain (lack a 3’ OH group)
175
Q

Special note about NRTI activation

A

Tenofovir is a nucleoTide analog and doesn’t have to be activated

Other NRTIs are nucleoSide analog and have to be phosphorylated to bec active

176
Q

Drug used for HIV prophylaxis and during pregnancy to reduce risk of fetal transmission

A

Zidovudine

- formerly known as AZT

177
Q

NRTI Toxicity

A 
Bone marrow suppression
- can be reversed with G-CSF and erythropoietin
Peripheral neuropathy
Lactic acidosis (nucleosides)
Anemia (ZDV/ AZT)
178
Q

Non- Nucleoside Reverse Transcriptase INhibitors

A

Nevirapine, Efavirenz, Delavirdine

179
Q

NNRTIs

A

bind to reverse transcriptase at site different from NRTIs

- do not require phosphorylation to be active or compete with nucleotides

180
Q

NNRTI Toxicity

A

Bone marrow suppression (can be reversed with G-CSF and erythropoietin)
Peripheral neuropathy
Rash

181
Q

Raltegravir

A

inhibits HIV genome integration into host cell chromosome by reversible inhibiting HIV integrase

** associated with hypercholestermias as toxicity

182
Q

Interferons

A
  • glycoproteins synthesized by virus-infected cells; block replication of both RNA and DNA viruses
183
Q

IFN-alpha as treatment

A
  • treats chronic hepatitis B and C, Kaposi’s sarcoma
184
Q

IFN-alpha

A

treats Multiple sclerosis

185
Q

IFN-gamma

A

treats NADPH oxidase deficiency

186
Q

IFN- Toxicity

A

Neutropenia, Myopathy

187
Q

Sulfonamide effect on pregnacy

A

Kernicterus (accumulation of bile in the brain - associated with sever jaundice in newborns)

188
Q

Aminoglycosides’ effect on pregnacy

A

Ototoxicity

189
Q

Floroquinolones’ effect on fetus

A

Cartilage damage

190
Q

Clarithromycin’s effect on fetus

A

Embryotoxic

191
Q

Tetracyclines’ effect on fetus

A

Discolored teeth

Inhibition of bone growth

192
Q

Ribavirin (antiviral) effect on fetus

A

Teratogenic

193
Q

Griseofulvin (anti-fungal) effect on fetus

A

Teratogenic

194
Q

Chloramphenicol effect on fetus

A

“Gray baby”

USMLE Step 1 (34 decks)

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