Antibiotics Flashcards

(104 cards)

1
Q

Sulphonamides consist of many different drugs. Give some examples

A

Antibiotics: sulfamethoxazole (SMX), sulfadiazine, sulfisoxazole

Nonantibiotic sulfonamides

  • Diuretics: thiazides, furosemide, acetazolamide
  • Anti-inflammatory drugs: sulfasalazine, celecoxib
  • Sulfonylureas
  • Probenecid
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2
Q

What are trimethoprim / sulfamethoxazole / cotrimoxazole used for?

A
Shigella
Salmonella
Empiric treatment for simple UTI
Prophylaxis and treatment of P. jirovecii (PCP)
Prophylaxis of toxoplasmosis
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3
Q

What are the risks of daptomycin?

A

Reversible myopathy
Rhabdomyolysis
Allergic pneumonitis
Hypersensitivity

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4
Q

What is clindamycin used for?

A
  • Anaerobes, such as Clostridium perfringens, Bacteroides spp. (clindamycin is less effective against Bacteroides than other anaerobic species) (aspiration pneumonia, lung abscesses, oral infections)
  • Group A streptococcus: especially invasive infections
  • Partially effective against gram-positive aerobes e.g. MRSA
  • Babesia (together with quinine)
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5
Q

Which Abx are broad spectrum?

A

Ampicillin
Co-amoxiclav
Piperacillin
3rd, 4th and 5th gen cephalosporins

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6
Q

What are the risks of carbapenems?

A
Secondary fungal infections
CNS toxicity: can lower seizure threshold at high serum concentrations (highest risk: imipenem) (lowest risk: meropenem)
Gastrointestinal upset
Rash
Thrombophlebitis
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7
Q

List 5 penicillins

A
Penicillin G (benzylpenicillin)
Penicillin V (phenoxymethylpenicillin)
Oxacillin
Nafcillin
Methicillin
Floxacillin
Dicloxacillin
Amoxicillin
Ampicillin
Piperacillin
Ticarcillin
Mezlocillin
Carbenicillin
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8
Q

What is pyrazinamide used for?

A

TB

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9
Q

What’s rifampin used for?

A
  • TB
  • Leprosy
  • M.avium-intracellulare

Meningococcal prophylaxis
Hib chemoprophylaxis

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10
Q

What is ethambutol used for?

A

M. TB

M. avium-intracellulare

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11
Q

What are penicillin G and penicillin V used for?

A
  • Gram-positive aerobes (esp. Streptococcus pyogenes, Streptococcus pneumoniae)
  • Gram-negative cocci (esp. Neisseria meningitidis)
  • Spirochetes (esp. Treponema pallidum)
  • Branching gram-positive anaerobes (especially Actinomyces)
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12
Q

Which Abx are CI in renal failure?

A
Epoxides
Aminoglycosides
Tetracyclines
Sulfonamides w/ diaminopyrimidines
Nitrofurans
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13
Q

Which Abx are CI in hepatic failure?

A
Tetracyclines
Macrolides (azithromycin and clarithromycin)
Sulfonamides with diaminopyrimidines
Nitrofurans
Pyrazinamide
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14
Q

How do fluoroquinolones like ciprofloxacin target bacteria?

A

DNA gyrase inhibition

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15
Q

What’s given for suspected bacterial meningitis in the community if penicillin allergic?

A

IV/IM cefotaxime

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16
Q

What is chloramphenicol used for?

A

Meningitis caused by H. influenzae, N. meningitidis, and/or S. pneumoniae

Rickettsia infections (e.g., Rocky Mountain spotted fever caused by Rickettsia rickettsii)

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17
Q

What are glycopeptide Abx like vancomycin used for?

A

Is effective against a wide range of gram-positive bacteria only
MRSA
S. epidermidis
Enterococci (if not vancomycin resistant enterococci)
C. difficile (causing pseudomembranous colitis): administered orally

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18
Q

What are the risks and contraindications of aminoglycosides like gentamicin?

A

Adverse effects

  • Nephrotoxicity
  • Ototoxicity and vestibulotoxicity (risk of ototoxicity is higher when used concurrently with loop diuretics) resulting in: tinnitus, ataxia, vertigo
  • Bc of toxicity risks and narrow therapeutic window, need to measure levels 6-14hrs after first dose
  • Neuromuscular blockade
  • Teratogenicity
Contraindications
Myasthenia gravis
Botulism
Pregnancy
Cautious use in patients with renal dysfunction
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19
Q

SEs of tetracyclines?

A

Nausea, diarrhoea, vomiting

Photosensitivity

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20
Q

What is co-trimoxazole? Give an example of what it’s used for

A

Trimethoprim and sulfamethoxazole

Used in PCP

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21
Q

What’s given for suspected bacterial meningitis in the community?

A

Single dose of IV/IM parenteral benzylpenicillin ASAP
 <1yo 300mg
 1-9yo 600mg
 >9yo 1200mg

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22
Q

Give 3 examples of macrolides

A

Erythromycin
Clarithromycin
Azithromycin

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23
Q

What are the risk of cephalosporins?

A

Potential cross-reactivity in patients with penicillin allergies (the rate is low even in patients with allergy to penicillin)
Autoimmune hemolytic anemia (AIHA)
Vitamin K deficiency, which increases the risk of bleeding
Disulfiram-like reaction, especially when consumed with alcohol (flushing, tachycardia, hypotension)
Increases nephrotoxic effect of aminoglycosides when administered together with cephalosporins
Neurotoxicity (can lower seizure threshold)

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24
Q

Side effects and CI of dapsone

A
Adverse effects
Methemoglobinemia
Triggers hemolytic anemia in patients with G6PD deficiency
Agranulocytosis
GI upset
Peripheral neuropathy

Contraindications
G6PD deficiency

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25
What are the side effects of amoxicillin and ampicillin?
``` D+V Pseudomembranous colitis Hypersensitivity reactions Drug-induced rash Cholestasis Possibly acute interstitial nephritis ```
26
What is linezolid (oxazolidinone) used for?
multidrug-resistant gram-positive bacteria (VRE, MRSA)
27
What is daptomycin used for?
Gram-positive bacteria S. aureus, especially MRSA Mainly used in skin and skin structure infections, bacteremia, and endocarditis Vancomycin-resistant Enterococci (VRE) Dap-to-my-cin is good to my skin: daptomycin is used to treat skin infections.
28
What are macrolides like erythromycin used for?
- Atypical pneumonia caused by: Mycoplasma pneumonia, Legionella pneumophila, Chlamydophila pneumoniae - Bordetella pertussis - STIs caused by Chlamydia - Gram-positive cocci especially for the treatment of streptococcal infection in patients who are allergic to penicillin) - Neisseria spp. (second-line prophylaxis for N. meningitidis; Dual therapy with ceftriaxone for N. gonorrhoeae (azithromycin)) - Mycobacterium avium - H. pylori (clarithromycin is the part of triple therapy) - Ureaplasma urealyticum - Babesia spp. (azithromycin in combination with atovaquone) - Can act as a pro-kinetic in ileus
29
When are monobactams like aztreonam used?
- Gram-ve bacteria | - Alternative if penicillin-allergic or can't take aminoglycosides bc of renal insufficiency
30
Diarrhoea and Abx - what do you suspect? What must you NOT give and why?
C. Diff! Do not give anti-diarrhoeals! Risk of toxic megacolon, perforation and death
31
What are the risks and contraindications of clindamycin?
Special considerations: cross-resistance with macrolides ``` Adverse effects GI upset (e.g., diarrhea) Pseudomembranous colitis Fever Teratogenicity ``` Contraindications: In pregnant women during the 1st trimester and breastfeeding women, clindamycin should be used only if benefits outweigh the risks
32
How are B-lactams ~ excreted?
Renally
33
What is piperacillin useful against?
- Gram-negative rods, especially Pseudomonas - Also effective against anaerobes (e.g., Bacteroides fragilis) - Gram-positive aerobes: not effective against S. viridians
34
Give 3 examples of tetracyclines
``` Tetracycline Doxycycline Minocycline Eravacycline Sarecycline Omadacycline Demeclocycline ```
35
Which Abx need levels measured and why? When do you measure levels?
Gentamicin Narrow therapeutic window Ototoxic and nephrotoxic at high levels Measure 6-14hrs after taking
36
What are tetracyclines like doxycycline used for?
- Bacteria that lack a cell wall (e.g, Mycoplasma pneumoniae, Ureaplasma) - Intracellular bacteria, such as Rickettsia, Chlamydia, or Anaplasma (tetracyclines accumulate intracellularly and are, therefore, effective against intracellular pathogens) - Borrelia burgdorferi - Other: Ehrlichia, Vibrio cholerae, Francisella tularensis - Cutibacterium acnes (topical tetracycline is used to treat acne) - Community-acquired MRSA (doxycycline)
37
What are the carbapenems used for?
Last-resort drugs (used only in life-threatening infections or after other antibiotics have failed) because of the significant adverse effects Broad-spectrum antibiotics with intrinsic beta-lactamase resistance - Gram-positive cocci; (except for MRSA and Enterococcus faecalis, which are intrinsically resistant) - Gram-negative rods, including Pseudomonas aeruginosa (except ertapenem which has limited activity against Pseudomonas) - Anaerobes
38
What route are amoxicillin and ampicillin commonly given?
AmOxicillin is administered Orally, while amPicillin is administered by a Prick (IV/IM)
39
Which Abx have good CNS penetration?
``` Ceftriaxone Aztreonam Linezolid Chloramphenicol Fluoroquinolones Metronidazole Trimethoprim ```
40
Which Abx can be used as pro-kinetics in ileus?
Macrolides like erythromycin
41
In hospital, what empirical Abx are given for suspected bacterial meningitis?
Options include IV 3rd gen cephalosporin like ceftriaxone or cefotaxime
42
What are the adverse effects and contraindications of chloramphenicol?
Adverse effects - Dose-dependent bone marrow suppression: aplastic anemia, leukopenia, and/or thrombocytopenia - Gray baby syndrome, ~ in premature babies (cyanosis, vomiting, flaccidity, hypothermia, shock) Contraindications Infancy Pregnancy Cautious use in patients with renal and/or hepatic dysfunction
43
What are B-lactams commonly given WITH and why?
Beta-lactamase inhibitors e.g. CATS: Clavulanate, Avibactam, Tazobactam, Sulbactam Gram -ve and anaerobes sometimes produce b-lactamases, so give a b-lactamase inhibitor to prevent the destruction of your b-lactam Abx
44
What are the clinical uses for amoxicillin and ampicillin?
Gram-positive aerobes Gram-negative rods (not effective against Enterobacter spp.) Aminopenicillin therapy HHEELPSSS against H. influenzae, H. pylori, E. coli, Enterococci, Listeria monocytogenes, Proteus mirabilis, Salmonella, Shigella, Spirochetes.
45
What are the uses of nitroimidazoles like metronidazole?
V. wide spectrum - good for anaerobes and protozoa Certain protozoa (e.g., Entamoeba histolytica, Giardia, Trichomonas) Anaerobes (e.g., C. difficile, Bacteroides spp.) Facultative anaerobes (Gardnerella vaginalis, Helicobacter pylori in place of amoxicillin (e.g., in case of penicillin allergy) as part of a triple therapy regimen) Not effective against aerobes Take the Metro To lonG BEaCH: Metronidazole treats Trichomonas, Giardia/Gardnerella, Bacteroides, Entamoeba, Clostridium, and H. pylori.
46
Which Abx for non-MRSA staph?
``` Penicillinase-resistant penicillins: Nafcillin Dicloxacillin Oxacillin Floxacillin Methicillin ``` NAF for STAPH
47
Trimethoprim is what class of antibiotic?
Diaminopyrimidine derivative
48
Which Abx are CI in children?
For SAFe Children, these Tablets are Contraindicated: Sulfonamides, Aminoglycosides, Fluoroquinolones, Clarithromycin, Tetracyclines, and Chloramphenicol are contraindicated in children.
49
Which Abx are CI in pregnancy?
Cut the Tablets for your Child's SAFety: Chloramphenicol, Tetracyclines, Clarithromycin, Sulfonamides, Aminoglycosides, and Fluoroquinolones are contraindicated in pregnancy Also pyrazinamide
50
Which Abx are anti-pseudomonal?
Antipseudomonal penicillins (e.g., piperacillin, ticarcillin)
51
1st and 2nd line for C. Diff?
Metronidazole | 2nd line = vancomycin (po - not IV)
52
What Abx for dog/cat bite?
Co-amoxiclav If penicillin allergic: doxycycline and metronidazole
53
In hospital, what empirical Abx are given for suspected bacterial meningitis if risk of listeria and >60yo/immunocompromised, but penicillin allergy?
Chloramphenicol if penicillin allergy If Listeria and >60yo/immunocompromised add trimethoprim/sulfamethoxazole if pen allergy
54
List the 5 classes of antimycobacterial drugs, and an example of each
- Rifamycins e.g. rifampin, rifabutin, rifaximin, rifapentine - Hydrazides e.g. isoniazid - Nicotinamides e.g. pyrazinamide - Ethylenediamine derivates e.g. ethambutol - Sulfones e.g. dapsone
55
In hospital, what empirical Abx are given for suspected bacterial meningitis if risk of penicillin-resistant pneumococci or travel in last 6m
Options include IV 3rd gen cephalosporin like ceftriaxone or cefotaxime If risk of penicillin-resistant pneumococci or travel in last 6m, you might want to add vancomycin or rifampicin
56
What are the adverse effects of trimethoprim?
Megaloblastic anemia Leukopenia, granulocytopenia (can be prevented with concomitant folinic acid administration) In high doses: hyperkalemia, particularly in HIV-positive patients Artificially increased creatinine (despite unchanged GFR) SEs: N+V, rashes
57
Describe neutropenic sepsis: criteria, when does it ~ present, typical organisms
Temp >38, neutrophils <0.5 (or 1) +/ features of sepsis ~ 5-10 days post-chemo, but can be up to months after ~ infection is from the gut (E. Coli, Klebsiella, Pseudomonas)
58
What are the risks and contraindications of linezolid (oxazolidinone)?
Adverse effects - GI upset - Pancytopenia (especially thrombocytopenia) due to bone marrow suppression - Peripheral neuropathy - Serotonin syndrome: Linezolid partially inhibits monoamine oxidase, which is responsible for the break down of neurotransmitters like serotonin. Contraindications - Concurrent use with MAOIs and SSRIs - Consider use in pregnant women only if benefits outweigh the risks, as safety in this population has not been established.
59
What are the risks and contraindications of tetracyclines
Adverse effects - Hepatotoxicity - Deposition in bones and teeth → inhibition of bone growth (in children) and discoloration of teeth - Damage to mucous membranes (e.g., esophagitis, GI upset) - Photosensitivity - Degraded tetracyclines are associated with Fanconi syndrome Contraindications - Children < 8 years of age (except doxycycline) - Pregnant women - Breastfeeding women Patients with renal failure (except doxycycline bc GI excreted instead of renally) - Cautious use in patients with hepatic dysfunction
60
How do sulfonamides and diaminopyrimidines like trimethoprim work?
Inhibit folic acid synthesis
61
Adverse effects and CI of pyrazinamide?
- Hyperuricaemia - Hepatotoxicity - Teratogenic CI: - hepatic failure - acute gout - pregnancy (teratogenic)
62
What are the uses for fluoroquinolones like ciprofloxacin?
Norfloxacin, ciprofloxacin, and ofloxacin: - Gram-negative rods causing urinary and gastrointestinal infections - Some gram-positive pathogens - Genitourinary infections caused by Neisseria gonorrhoeae, Chlamydia trachomatis, and/or Ureaplasma urealyticum - Ciprofloxacin: Pseudomonas aeruginosa (e.g., malignant otitis externa, HAP) Levofloxacin, moxifloxacin, and gemifloxacin: - Atypical bacteria (e.g., Legionella spp., Mycoplasma spp., - Chlamydophila pneumoniae) - Also effective against anaerobes - Gemifloxacin is highly potent against penicillin-resistant pneumococci. - Moxifloxacin: 2nd-line treatment of tuberculosis in patients who cannot tolerate antitubercular drugs and in multidrug resistant tuberculosis
63
What are the risks and contraindications for fluoroquinolones like ciprofloxacin?
Adverse effects - GI upset - Neurological symptoms (mild headache, dizziness, mood changes, peripheral neuropathy, can lower seizure threshold (increased risk in patients taking NSAIDs and those with a previous history of epilepsy)) - Hyperglycemia / hypoglycemia - QT prolongation - Photosensitivity - Skin rash - Superinfection (most commonly with gram-positive pathogens) - Potentially life-threatening exacerbations in patients with myasthenia gravis - In children: potential damage to growing cartilage → reversible arthropathy - Muscle ache, leg cramps, tendinitis, tendon rupture, especially of the Achilles tendon (the risk of tendon rupture is higher for individuals over 60 years of age and for individuals on steroid therapy) Contraindications - Children and teenagers < 18 years of age - Patients > 60 years of age and those taking cortisol - Pregnant women - Breastfeeding women - Epilepsy, stroke, CNS lesions/inflammation - QT prolongation - Myasthenia gravis - Cautious use in patients with: renal failure, hepatic failure, antacid use, known aortic aneurysm or increased risk of aneurysms (e.g., Marfan syndrome, Ehlers-Danlos syndrome, advanced age, peripheral atherosclerotic disease, hypertension)
64
How do b-lactams work?
Inhibit cell wall synthesis -> bactericidal
65
Give 3 examples of fluoroquinolones
``` Norfloxacin Moxifloxacin Gemifloxacin Ciprofloxacin Ofloxacin Levofloxacin Enoxacin Nalidixic acid Gatifloxacin ```
66
Which Abx can lower the seizure threshold?
fluoroquinolones like ciprofloxacin cephalosporins carbapenems
67
Which Abx disrupt cell membrane integrity?
Lipopeptides (daptomycin) | Polymyxins
68
If someone is allergic to penicillin, which other Abx might you not be able to use? How do you decide if they're ok to use?
Penicillin allergic -> can also be cephalosporin allergic, but depends on how bad a reaction you have to penicillin o Minor reaction or minor rash might be ok w/ cephalosporins o Severe reaction or anaphylaxis -> avoid cephalosporins
69
Side effects and contraindications of rifampin?
- Red-orange discolouration of body fluids - Flu-like Sx - Minor hepatotoxicity The 6Rs of Rifampin: Red or orange urine, RNA polymerase Repression, Ramping up of cytochrome P450 activity, and Rapid Resistance development if used alone. Contraindicated in breast feeding
70
Which Abx inhibit protein synthesis by binding to the 30S and 50s ribosomal subunits?
30S: Aminoglycosides Tetracyclines Glycylcylines (tetracycline derivative) ``` 50S: Macrolides Ketolides Lincosamides Streptogramins Oxazolidinones Amphenicols ```
71
Give 2 examples of glycopeptide Abx
``` Vancomycin Bacitracin Telavancin Dalbavancin Oritavancin ```
72
How can you test for C. Diff?
GDH (glutamate dehydrogenase) tells you if they're colonised w/ C. Diff Test for the exotoxins to see if active infection
73
What are the risks of nitroimidazoles like metronidazole?
Adverse effects - Headache - Disulfiram-like reaction: a systemic reaction occurs when metronidazole is consumed with alcohol -> immediate hangover-like Sx after alcohol ingestion, and Sx like flushing, tachycardia, hypotension, N+V, palpitations - Metallic taste - Peripheral neuropathy (particularly with prolonged use)
74
Give an example of a lipopeptide antibiotic
Daptomycin
75
Clindamycin is which class of antibiotic?
Lincosamide
76
Side effects and CI of ethambutol
- Optic neuropathy with decreased visual acuity and red-green color blindness which may result in irreversible blindness - Resistance develops rapidly if used as monotherapy CI: - unable to report visual changes - optic neuritis
77
Side effects of isoniazid
- Hepatotoxicity - Anion gap metabolic acidosis - Drug-induced lupus erythematosus - High doses can precipitate benzodiazepine-refractory seizures - Vitamin B6 deficiency: INH should be administered with pyridoxine to avoid vitamin B6 deficiency -> peripheral neuropathy, sideroblastic anemia, aplastic anemia, thrombocytopenia, optic neuropathy, pellagra
78
How do nitroimidazoles like metronidazole target bacteria?
Disrupt DNA integrity
79
Which Abx are CI in breastfeeding?
``` Aminoglycosides Tetracyclines Glycylcyclines Lincosamides Chloramphenicol Fluoroquinolones Sulfonamides with diaminopyrimidines Nitrofurans Rifamycins ```
80
Give an example of each of the generations of cephalosporin
1st gen: cephalexin, cefazolin 2nd gen: cefuroxime, cefaclor, cefoxitin, cefotetan 3rd gen: ceftriaxone, cefotaxime, ceftazidime, cefixime, cefpodoxime 4th gen: cefepime 5th gen: ceftaroline
81
Give 4 examples of aminoglycosides
``` Gentamicin Amikacin Tobramycin Streptomycin Neomycin ```
82
In hospital, what empirical Abx are given for suspected bacterial meningitis if risk of listeria and >60yo/immunocompromised?
Options include IV 3rd gen cephalosporin like ceftriaxone or cefotaxime If Listeria and >60yo/immunocompromised, add amoxicillin
83
In hospital, what empirical Abx are given for suspected bacterial meningitis if penicillin allergic?
IV Chloramphenicol
84
Give an example of an oxazolidinone?
Linezolid
85
When do you give Abx for cat/dog bites?
If it looks infected Prophylactically if: - need surgical repair - sensitive area e.g. hands/face - close to bone/joints - immunocompromised (inc. DM) - deep / significant wound
86
What are the differences in which bacteria are targeted by the different cephalosporins?
Gram +ve: 1st, 4th and 5th gen Gram -ve: all, but 3rd-5th gen are ESBL MRSA, Listeria and Enterococcus: 5th gen Pseudomonas: 3rd and 4th gen
87
What is tazocin?
Piperacillin/tazobactam
88
What is nitrofurantoin used for?
Urinary tract pathogens - Gram-positive: Enterococci, Staphylococcus saprophyticus, group B streptococcus, Staphylococcus aureus, Staphylococcus epidermidis - Gram-negative: E. coli, Enterobacter spp., Shigella spp., Salmonella spp., Citrobacter spp, Neisseria spp, Bacteroides spp., Klebsiella spp. Not effective against Pseudomonas and/or Proteus Clinical indications include: - Treatment and prophylaxis of acute uncomplicated UTIs (e.g., urethritis, cystitis) - Asymptomatic bacteriuria or symptomatic UTI in pregnant women - Should not be used in (suspected) pyelonephritis because nitrofurantoin does not achieve adequate concentration in renal tissue
89
Give 2 examples of carbapenems
Imipenem Meropenem Ertapenem Doripenem
90
What are the risks and contraindications of macrolides like erythromycin?
Risks (MACROlides include gastrointestinal Motility issues, Arrhythmia (due to prolonged QT interval), acute Cholestatic hepatitis, Rash, and eOsinophilia) - Increased intestinal motility → GI upset (n+v+d) - QT-interval prolongation (esp. erythromycin), arrhythmia - Acute cholestatic hepatitis - Eosinophilia - Rash - Beware erythromycin increases the effects of oral anticoagulants like warfarin - Hepatotoxicity from azithromycin Contraindications - Erythromycin estolate and clarithromycin are contraindicated in pregnant women (potentially hazardous to the fetus) - Azithromycin and clarithromycin are contraindicated in patients with hepatic failure (erythromycin should be used cautiously). - Caution in paeds, breastfeeding, renal failure
91
eradication Tx for H. Pylori?
Metronidazole Amoxicillin PPI
92
What is isoniazid used for?
TB
93
What are aminoglycosides like gentamicin used for?
- Severe gram-negative rod infections - Not effective against anaerobes (aminoglycosides require oxygen to be absorbed by cells) - Neomycin, which is not absorbed systemically, is administered orally to prepare the gut for bowel surgery. - Streptomycin is used as a second-line treatment for Mycobacterium tuberculosis and M. avium-intracellulare
94
What are the adverse effects of contraindications of nitrofurantoin?
``` Adverse effects Pulmonary fibrosis Hemolytic anemia in patients with G6PD deficiency GI upset Reversible peripheral neuropathy ``` Contraindications Children < 1 month of age Breastfeeding women Women at 38–42 weeks' gestation or during delivery Hepatic dysfunction Renal dysfunction with a creatinine clearance < 60 mL/min
95
1st line Abx for TB?
Rifampicin Isoniazid Pyrazinamide Ethambutol
96
Which Abx commonly cause C. Diff?
Clindamycin Cephalosporins Quinolones Broad-spectrum penicillins
97
1st, 2nd and 3rd line for neutropenic sepsis? When do you use 2nd and 3rd line?
1: Piperacillin/Tazobactam (Tazocin) 2: Ceftazidime (if minor reaction to penicillins e.g. minor rash) 3. Meropenem (if major reactions to penicillins e.g. severe reaction / anaphylaxis)
98
What are the risks of glycopeptide Abx like vancomycin?
Intravenous administration - Nephrotoxicity - Ototoxicity/vestibular toxicity - Thrombophlebitis - Red man syndrome: an anaphylactoid reaction caused by rapid infusion of vancomycin (diffuse flushing of the skin, pruritus mainly of the upper body, muscle spasms and pain in the back and chest, -possible hypotension and dyspnea) - DRESS syndrome - Neutropenia - Dysgeusia and gastrointestinal side effects (e.g., nausea, vomiting, abdominal pain) Oral administration: predominantly dysgeusia and gastrointestinal side effects
99
What is dapsone used for?
- M. leprae - PCP - Dermatitis herpetiformis - Toxoplasmosis - Malaria
100
When are polymyxin Abx used?
Severe gram -ve infections caused by multidrug-resistant gram-negative bacteria
101
Metronidazole is what class of antibiotic?
Nitroimidazole
102
Which antibiotics are b-lactams?
Penicillins Cephalosporins Carbapenems Monobactams
103
Abx for chlamydia - when would you choose which to give?
- Doxycycline 7/7 BD = 1st line, but not safe in pregnancy - Azithromycin 3/7 can be given if you're uncertain about compliance, but also unsafe in pregnancy - Erythromycin can be given in pregnancy
104
Which classes of antibiotics inhibit cell wall synthesis?
B-lactams (penicillins, cephalosporins, carbapenems, monobactams) Glycopeptides Epoxides