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Yr 3 - Pharmacology > Drugs - Antibiotics > Flashcards

Drugs - Antibiotics Flashcards

1
Q

What class of drug are penicillins?

A

Beta lactams

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2
Q

Mechanism of pencillins?

A

1) Inhibit cell wall synthesis -> penicillins inhibit enzymes responsible for cross-linking peptidoglycans in bacterial cell walls via their beta lactam ring
2) This weakens cell walls leading to uncontrolled entry of water into bacteria -> cell swelling, lysis, and death (bactericidal)

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3
Q

What is penicillinase?

A

Bacteria can produce beta-lactamases (penicillinase) which break the beta-lactam ring, creating resistance

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4
Q

Which bacteria produce penicillinases?

A

most strains of Staphylococcus

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5
Q

Patients with an immediate hypersensitivity reaction to penicillins may also react to which other Abx? Why?

A

Cephalosporins and carbapenems (as all beta-lactams)

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6
Q

How are penicillins eliminated?

A

renally (caution in renal impairment)

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7
Q

Which drug do penicillins majorly interact with? How?

A

Methotrexate - All penicillins reduce the renal excretion of methotrexate, increasing the risk of toxicity.

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8
Q

What phenoxymethylpenicillin also known as?

A

Penicillin V

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9
Q

Are benzylpenicillin and penicillin V narrow or broad spectrum?

A

Relatively narrow (often combined with other Abx)

  • Activity against some Gram-positive organisms (e.g. streptococci)
  • Activity against some Gram-negative cocci (e.g. Neisseria meningitidis, Neisseria gonorrhoea)
  • NOT active against Gram-negative bacilli (rods)
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10
Q

Which bacteria is benzylpenicillin most effective against?

A
  • Group A strep (s. pyogenes / b-haemolytic streptococcus)
  • S. pneumoniae
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11
Q

What are some indications for benzylpencillin

A
  • Streptococcal infections:
    • Tonsilitis (Group A Strep aka S. pyogenes aka b-haemolytic streptococcus)
    • Pneumonia (S. pneumoniae) – with a macrolide or tetracycline
    • Endocarditis – usually with gentamicin
    • Skin and soft tissue infections – with flucloxacillin
  • Meningococcal infections:
    • Meningitis
    • Septicaemia
  • Clostridial infection (Gas gangrene - clostridial myonecrosis)
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12
Q

Is a delayed reaction to penicillin (7-10 days after initial exposure or 1-2 days after repeated exposure) IgG or IgM mediated?

A

IgG

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13
Q

Is an immediate reaction to penicillin IgG or IgE mediated?

A

IgE

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14
Q

Is anaphylaxis IgG or IgM mediated?

A

IgE

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15
Q

What is the only way in which benzylpenicillin can be administered?

A

Injection (IV or IM)

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16
Q

A young person presents with a sore throat caused by an unknown organism.

Should you use a) amoxicillin or b) penicillin V

Why?

A

Penicillin V - if sore throat is due to EBV, amoxicillin commonly causes a rash which can lead to false label of penicillin allergy

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17
Q

What ingredients does co-amoxiclav contain?

A

Amoxicillin + clavulanic acid

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18
Q

Purpose of clavulanic acid in co-amoxiclav?

A

Protects them against the hydrolysis of their beta-lactam ring and so rendering them effective against beta-lactamase producing bacteria.

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19
Q

Indications for amoxicillin?

A
  • Susceptible infections such as:
    • Uncomplicated pneumonia
    • Otitis media
    • Sinusitis
    • UTIs
  • Triple therapy for H. pylori peptic ulcer disease
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20
Q

What triple therapy is used in H. pylori peptic ulcer?

A

2x Abx + 1x PPI

Amoxicillin + clarithromycin/metronidazole + omeprazole

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21
Q

Indications for co-amoxiclav?

A

Common choice for severe, resistant and hospital-acquired infections:

  • Respiratory tract infections (e.g. severe pneumonia)
  • Genitourinary & abdominal infections
  • Cellulitis
  • Bone & joint infections
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22
Q

Why is amoxicillin not generally used empirically?

A

Due to risk of bacterial resistance as broad spectrum

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23
Q

Is amoxicillin broad or narrow spectrum?

A

Broad - spectrum of activity against a wide range of gram-positive and gram-negative cocci and bacilli.

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24
Q

Why do broad spectrum Abx incur the risk of Abx-associated colitis?

A

Broad-spectrum Abx kill normal gut flora, allowing overgrowth of toxin-producing Clostridium difficile

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25
Q

General side effects of penicillins?

A
  • Allergy
  • GI upset
  • Abx associated colitis
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26
Q

Specific side effects of co-amoxiclav?

A
  • Acute liver injury (cholestatic jaundice or hepatitis) – can occur after co-amoxiclav treatment but is generally self-limiting
  • Liquid co-amoxiclav can stain teeth
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27
Q

Contraindications of amoxicillin/co-amoxivlac?

A
  • Allergy
  • Caution in those at risk of C. difficile infection (in hospital, elderly)
  • Caution in those with history of penicillin-associated liver injury
  • Reduce dose in severe renal impairment
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28
Q

How do broad spectrum Abx affect warfarin?

A

Broad spectrum Abx enhance the effect of warfarin by killing the normal gut flora that synthesise vitamin K → enhanced risk of bleeding

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29
Q

Method of administration of amoxicillin i severe vs moderate-mild infections (no systemic upset)?

A

Severe → IV

Mild-moderate → oral

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30
Q

In co-amoxiclav 500/125, what is the dose of amoxicillin and clavulanic acid?

A

Amoxicillin → 500mg

Clavulanic acid → 125mg

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31
Q

Which penicillin is resistant to penicillinases (i.e. not inactivated by these enzymes produced by bacteria)?

A

Flucloxacillin

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32
Q

What type of bacteria commonly produce pencillinases?

A

Staphylococci

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33
Q

Which penicillin is effective against penicillin resistant staphylococci?

A

Flucloxacillin

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34
Q

Indications for flucloxacillin?

A
  • Skin and soft tissue infections – e.g. cellulitis
  • Osteomyelitis and septic arthritis
  • Other infections, including endocarditis
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35
Q

Is spectrum of flucloxacillin wide or narrow?

A

Penicillinase resistant Abx have a narrow spectrum of activity against Gram-positive staphylococci

Active against staphylococci only so are often combined with other Abx (e.g. benzylpenicillin in severe cellulitis)

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36
Q

Is MRSA resistant to flucloxacillin?

A

Yes

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37
Q

How are penicillins excreted?

A

Renally

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38
Q

Half life of flucloxacillin?

A

Rapid (45-60 minutes)

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39
Q

What class of Abx are cephalosporins & carbapenems

A

beta lactams

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40
Q

Give some examples of cephalosporins

A

cefuroxime, cefalexin, cefotaxime

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41
Q

Give some examples of carbapenems

A

meropenem, ertapenem

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42
Q

Indications for oral cephalosporins?

A

2nd & 3rd line options for treatment of urinary and respiratory tract infections

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43
Q

Indications for parenteral cephalosporins and carbapenems?

A

reserved for infections that are very severe or complicated, caused by antibiotic-resistant organisms

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44
Q

Spectrum of carbapenems & cephalosporins?

A

Broad spectrum

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45
Q

Typical Abx treatment of Pseudomonas infection?

A

Pseudomonas infection can be treated with a combination of an antipseudomonal beta-lactam (eg, penicillin or cephalosporin) and an aminoglycoside).

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46
Q

Side effects of cephalosporins & carbapenems?

A
  • N&V, diarrhoea
  • Antibiotic-associated colitis - tends to occur more commonly with 2nd and 3rd generation cephalosporins – their use is generally restricted
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47
Q

Contraindications for carbapenems & cephalosporins

A
  • Allergy to penicillin, cephalosporin or carbapenem
  • Caution in those at risk of C. diff infection (in hospital, elderly)
  • Use carbapenems with caution in those with epilepsy
  • Dose reduction required in those with renal impairment
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48
Q

Effect of carbapenems & cephalosporins on warfarin?

A

Can enhance the anticoagulant effect of warfarin by killing normal gut flora that synthesise vitamin K

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49
Q

Do cephalosporins or carbapenems interact with aminoglycosides? How?

A

Cephalosporins → may increase nephrotoxicity of aminoglycosides

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50
Q

Do cephalosporins or carbapenems interact with valproate? How?

A

Carbapenems → reduce plasma concentration and efficacy of valproate

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51
Q

Interaction between carbapenems and sodium valproate?

A

Carbapenem antibacterial agents (meropenem, ertapenem, and imipenem) cause reductions in serum valproate levels of up to 90% within 24-hours of carbapenem initiation

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52
Q

What class of Abx is clarithromycin and erythromycin?

A

Macrolides

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53
Q

Which Abx is indicated in severe pneumonia alongside a penicillin to cover atypical organisms including Legionella pnuemophila and Mycoplasma pneumoniae?

A

A macrolide e.g. clarithromycin

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54
Q

What are macrolides prescribed alongside in eradication of H. pylori?

A

PPI (e.g. omeprazole) + amoxicillin or metronidazole (in penicillin allergy)

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55
Q

When are macrolides used in the treatment of respiratory, skin and soft tissue infections ?

A

As an alternative to penicillin when use is contraindicated e.g. allergy

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56
Q

Which macrolide was isolated from Streptomyces erythraeus and which is synthetic?

A

Erythromycin → isolated from Streptomyces erythraeus

Clarithromycin → synthetic

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57
Q

What do synthetic macrolides have increased activity against?

A

have increased activity against Gram-negative bacteria, particularly Hameophilus influenzae

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58
Q

Are macrolides bacteriostatic or bactericidal?

A

Bacteriostatic → inhibit bacterial protein synthesis

59
Q

Which macrolide are side effects more common and severe with?

A

Erythromycin

60
Q

What can macrolides cause when given IV?

A

Thrombophlebitis

61
Q

What is the primary risk factor for C. diff colitis?

A

previous exposure to antibiotics

62
Q

What are the 4 most common commonly implicated agents in C. diff colitis?

A

cephalosporins (especially second and third generation)

fluoroquinolones

ampicillin/amoxicillin

clindamycin

63
Q

Which Abx is used to treat C. diff colitis?

A

Vancomycin

64
Q

Most common Abx to cause cholestatic jaundice?

A

Co-amoxiclav

65
Q

How do macrolides interact with the P450 system?

A

Are inhibitors of the P450 system

66
Q

Effect of taking macrolides with statins?

A

increased risk of myopathy

67
Q

Effect of taking macrolides with statins?

A

increased risk of myopathy

68
Q

Effect of taking macrolides with warfarin?

A

increased risk of bleeding

69
Q

In patients with LRTIs, when should macrolides generally only be added to penicillin treatment? Why?

A

When → Macrolides should generally only be added to penicillin treatment if there is evidence of pneumonia (e.g. consolidation on CXR).

Why → Macrolides are required to cover penicillin-resistant atypical organisms (e.g. Legionella pneumophila and Mycoplasma pnuemoniae) which cause pneumonia but do NOT cause other LRTIs e.g. COPD exacerbations.

70
Q

What organisms do macrolides cover in pneumonia?

A

Macrolides are required to cover penicillin-resistant atypical organisms (e.g. Legionella pneumophila and Mycoplasma pnuemoniae) which cause pneumonia but do NOT cause other LRTIs e.g. COPD exacerbations.

71
Q

Give some examples of aminoglycosides

A

Gentamicin, Amikacin, Neomycin

72
Q

What are systemic aminoglycosides usually used to treat?

A

Severe infections, particularly those caused by Gram-negative aerobes (including Pseudomonas** **aeruginosa):

  • Severe sepsis
  • Pyelonephritis and complicated UTI
  • Biliary and other intraabdominal sepsis
  • Endocarditis
73
Q

Are aminoglycosides bacteriostatic or bactericidal?

A

Bactericidal → bind irreversibly to bacterial ribosomes and inhibit protein synthesis

74
Q

Aminoglycosides main clinically relevant activity is against what type of bacteria?

A

Gram-negative aerobic bacteria

75
Q

What bacteria are aminoglycosides inactive against?

A

Inactive against streptococci and anaerobes so should be combined with penicillin and/or metronidazole when organism is unknown

76
Q

Why are aminoglycosides effective against aerobic bacteria?

A

Enter bacterial cells via an O2-dependent transport system (aerobes)

77
Q

Give 2 main side effects of aminogylcosides

A
  1. Nephrotoxicity
  2. Ototoxicity
78
Q

How do aminoglycosides cause nephrotoxicity?

A

Can accumulate in tubular epithelial cells where they trigger apoptosis and cell death

79
Q

How does nephrotoxicity caused by aminoglycosides typically present?

A

Can present as reduced urine output and rising serum creatinine and urea.

80
Q

How do aminoglycosides cause ototoxicity?

A

can accumulate in cochlear and vestibular hair cells where they trigger apoptosis and cell death

81
Q

How does ototoxicity caused by aminoglycosides typically present?

A

Often not noticed until after resolution of acute infection when patient may complain of hearing loss, tinnitus (cochlear damage) and/or vertigo (vestibular damage)

May be irreversible.

82
Q

How are aminoglycosides excreted?

A

Renally

83
Q

How are macrolides excreted?

A

Hepatic

84
Q

2 main contraindications for amiglycosides?

A
  • Renally excreted – caution in renal impairment, elderly and neonates
  • Can impair neuromuscular transmission – avoid in myasthenia gravis
85
Q

Ototoxicity is more likely if aminoglycosides are co-prescribed with which 2 drug classes?

A
  1. Furosemide
  2. Vancomycin
86
Q

Nephrotoxicity is more likely if aminoglycosides are co-prescribed with which 3 drug classes?

A
  1. Vancoymycin
  2. Ciclosporin
  3. Cephalosporin
87
Q

How are systemic aminoglycosides typically administered? Why?

A

IV → do not cross lipid membrane so are not absorbed from the gut (systemic therapy must be given parenterally

88
Q

What can be done to limit risk of toxicity when prescribing aminoglycosides?

A

Treatment duration should be as short as possible to limit toxicity – often a single dose and usually <7 days

89
Q

What class of Abx is vancomycin?

A

Glycopeptide

90
Q

What type of bacteria is vancomycin effective against?

A

Gram-positive infection notably Staphylococcus spp. (including MRSA), Streptococcus spp. and C. difficile

NO activity against Gram-negative organisms

91
Q

2 main indications for vancomycin?

A
  • Gram-positive infection e.g. endocarditis, where infection is severe and/or penicillins cannot be used due to resistance (e.g. MRSA) or allergy
  • Treatment of antibiotic-associated colitis caused by C. difficile infection
92
Q

1st line Abx management of MRSA?

A

Glycopeptides → vancomycin or teicoplanin

93
Q

MOA of vancomycin?

A

Inhibits growth and cross-linking of peptidoglycan chains, inhibiting synthesis of cell wall of Gram-positive bacteria (bactericidal)

94
Q

What is red man syndrome?

A

If vancomycin is infused rapidly, a rate-related reaction can occur caused by mast cell degranulation:

  • Generalised erythema
  • Hypotension
  • Bronchospasm
95
Q

Pathophysiology behind red man syndrome?

A

Mast cell degranulation

96
Q

The risk of ototoxicity and nephrotoxicity of vancomycin is increased when prescribed with which 3 drugs?

A
  1. Aminoglycosides
  2. Loop diuretics
  3. Ciclosporin
97
Q

For systemic infection, how must vancomycin be administered?

A

IV → large, hydrophobic molecule that is poorly absorbed across lipid membranes

98
Q

For treatment of C. difficile colitis, NICE recommends which Abx for 1st episode of mild-moderate infection, and which for recurrent, severe or metronidazole-resistant infection?

A

Mild → metronidazole

Severe → vancoymcin

99
Q

Give 2 examples of tetracylines

A

Doxycycline, Lymecycline

100
Q

Give 3 main indications for tetracyclines

A
  1. Acne vulgaris (oral)
  2. LRTIs
  3. Chlamydial infection e.g. PID
101
Q

What LRTIs are tetracyclines indicated in?

A

infective exacerbations of COPD (e.g. Haemophilus influenzae), pneumonia and atypical pneumonia (mycoplasma, Chlamydia psittaci, Coxiella burnetti)

102
Q

Spectrum of tetracyclines?

A

Relatively broad spectrum against many Gram-positive and negative organisms

103
Q

Why are tetracylines contraindicated in pregnancy, breastfeeding and children <12 y/o?

A

Tetracyclines bind to teeth & bones during development

Can lead to staining of teeth +/- hypoplasia/weakening of enamel

104
Q

What should tetracyclines not be given within 2 hours of?

A

Calcium, antacids or iron which will prevent antibiotic absorption → tetracyclines bind to divalent cations

105
Q

Tetracyclines & the sun?

A

Increased sensitivity to sun → wear SPF even on cloudy days

106
Q

Give some examples of quinolones

A

Ciprofloxacin, Monifloxacin, Levofloxacin

107
Q

3 main indications for quinolones?

A
  • Urinary tract infections – most commonly Gram-negative organisms
  • Severe gastroenteritis (e.g. due to Shigella, Campylobacter)
  • Lower respiratory tract infection (LRTI) – Gram-positive and Gram-negative organisms
108
Q

Why is ciprofloxacin unusual among oral Abx?

A

As it has significant activity against Pseudomonas aeruginosa

109
Q

MOA of quinolones?

A

Quinolones kill bacteria by inhibiting DNA synthesis (bactericidal)

110
Q

How do bacteria rapidly develop resistance against quinolones?

A

Resistance genes are spread horizontally between bacteria

111
Q

Side effects of quinolones?

A
  • GI upset – quinolones** and **cephalosporins are the broad-spectrum Abx more associated with C. difficile colitis
  • Delayed hypersensitivity reactions
  • Neurological effects (lowering of seizure threshold, hallucinations)
  • Inflammation & rupture of muscle tendons
  • Prolong QT interval – increased risk of arrythmias
112
Q

How does ciprofloxacin interact with the P450 system?

A

Ciprofloxacin is a cytochrome P450 inhibitor → increases toxicity of certain drugs, notably theophylline

113
Q

What class of Abx is ciprofloxacin?

A

Quinolone

114
Q

Effect of co-prescription of NSAIDs and ciprofloxacin?

A

Increases risk of seizures

115
Q

Effect of co-prescription of prednisolone and ciprofloxacin?

A

increases risk of tendon rupture/tendonitis

116
Q

4 main indications for metronidazole?

A
  • Antibiotic associated colitis
  • Oral infections (e.g. dental abscesses) or aspiration pneumonia caused by the Gram-negative anaerobes from the mouth
  • Surgical and gynaecological infections caused by the Gram-negative anaerobes from the colon e.g. Bacteroides fragilis
  • Protozoal infections e.g. trichomonal vaginal infection, amoebic dysentery, giardiasis
117
Q

What type of bacteria is C. diff?

A

Gram-positive anaerobe

118
Q

1st line Abx for giardiasis?

A

Metronidazole

119
Q

Spectrum of metronidazole?

A

Anaerobic bacteria and protozoa

120
Q

Side effect of metronidazole at high doses?

A

Neurological effects at high doses e.g. peripheral and optic neuropathy, seizures and encephalopathy

121
Q

What is metronidazole metabolised by?

A

metabolised by the cytochrome P450 system so dose should be reduced in those with hepatic impairment

122
Q

Interaction between metronidazole and alcohol?

A

Metronidazole inhibits the enzyme acetaldehyde dehydrogenase which is responsible for clearing the intermediate alcohol metabolite acetaldehyde from the body

123
Q

Which Abx is alcohol contraindicated in?

A

Metronidazole (during or for 48 hours after)

124
Q

Effect of metronidazole on P450 system?

A

Metronidazole has some inhibitory effect on CYP enzymes:

  • Reduces metabolism of warfarin → increases risk of bleeding
  • Reduces metabolism of phenytoin → increases risk of phenytoin toxicity
125
Q

Indications for topical chloramphenicol?

A
  • Bacterial conjunctivitis using eye drops or ointment
  • Otitis externa using ear drops
126
Q

Why is systemic chloramphenicol rarely used in UK?

A

Due to its toxicity → carries a significant risk of bone marrow toxicity which takes 2 forms:

  • Dose-related bone marrow suppression
  • Aplastic anaemia
127
Q

What is systemic chloramphenicol reserved for?

A

It is restricted to the treatment of life-threatening infection and only where other Abx classes cannot be used e.g. occasional cases of epiglottitis (Haemophilus influenzae) and typhoid fever (Salmonella spp)

128
Q

What needs to be closely monitored in systemic chloramphenicol?

A

FBC needs to be monitored closely

129
Q

A 22 y/o woman complains of dysuria. Her GP diagnoses an uncomplicated UTI. Her only medication is the COCP and she has not missed any doses of this. She has no allergies. What is the most appropriate treatment?

  1. Cefotaxime
  2. Ciprofloxacin
  3. Clarithromycin
  4. Gentamicin
  5. Trimethoprim
A

Trimethoprim

130
Q

Why are macrolides not effective in UTIs?

A

Have little activity against Gram-negative organisms that typically cause UTIs (E. coli)

131
Q

What is used as 2nd/3rd line for UTI or for complicated UTI’s?

A

Ciprofloxacin

132
Q

A 72 y/o woman is admitted to hospital with severe cellulitis of her right leg. She has no allergies. What is the most appropriate treatment?

  1. Amoxicillin + clarithromycin
  2. Benzylpenicillin + flucloxacillin
  3. Cefotaxime + acyclovir
  4. Co-amoxiclav + metronidazole
  5. Co-amoxiclav + gentamicin
A

Benzylpenicillin + flucloxacillin

133
Q

Why is benzylpenicillin added to flucloxacillin in severe cellulitis?

A

SSTIs are usually caused by S. aureus and group A streptococcus (e.g. S. pyogenes)

  • S. aureus → usually sensitive to flucloxacillin (a penicillinase-resistant penicillin)
  • Group A strep → usually sensitive to benzylpenicillin (a ‘standard’ penicillin)
134
Q

What would cefotaxime + acyclovir be prescribed in?

A

used in suspected intracranial infection to cover bacterial meningitis and viral encephalitis, pending a diagnosis from lumbar puncture

135
Q

An 83 y/o woman is admitted to the acute medical unit with a diagnosis of mild CAP (CURB-65 score 1). Her mobility is poor, but she has no active co-morbidities, does not usually take any medications and has no allergies. What would be the most appropriate Abx to treat her infection?

  1. Cefotaxime
  2. Ciprofloxacin
  3. Doxycycline
  4. Ertapenem
  5. Flucloxacillin

Why?

A

Doxycycline

The ‘best guess’ Abx for pneumonia should therefore ideally have broad spectrum of activity to cover all these possibilities.

Doxycycline (a tetracycline) is suitable as it covers Gram-positive, Gram-negative, and atypical organisms.

136
Q

A 75 y/o man is being treated for a UTI. He has no other medical problems and takes no regular medications. He has no allergies. The results of his urine microscopy have returned. The bacterial sensitivities suggest any B-lactam Abx would be suitable. What Abx should be prescribed?

  1. Amoxicillin
  2. Ciprofloxacin
  3. Clarithromycin
  4. Doxycycline
  5. Metronidazole
A

Amoxicillin

137
Q

A 60 y/o woman is admitted with fever, confusion and seizures. A decision to treat her empirically for HSV viral encephalitis is made. What is the most appropriate treatment?

  1. Aciclovir
  2. Amoxicillin
  3. Ceftriaxone
  4. Dexamethasone
  5. Fluconazole
A

Aciclovir

138
Q

In what cases of meningitis is amoxicillin indicated in?

A

Listeria monocytogenes (very young and very old)

139
Q

What is 1st line Abx for bacterial meningitis?

A

Ceftriaxone

140
Q

What can improve outcomes in those with suspected pneumococcal meningitis ?

A

Dexamethasone

141
Q

A 77 y/o man with MS is admitted as an emergency with urinary sepsis. He has a long-term suprapubic catheter for the treatment of urinary retention. Urine cultures grew Pseudomonas aeruginosa. What Abx is most likely to be active against this organism?

  1. Amoxicillin
  2. Cephalexin
  3. Ciprofloxacin
  4. Nitrofurantoin
  5. Trimethoprim
A

Ciprofloxacin

142
Q

Hospital guidelines indicate that patients who are immunocompromised e.g. by neutropenia, who develop infection should be treated with bactericidal rather than bacteriostatic Abx. Which Abx has a consistently bactericidal mechanism of action?

  1. Amoxicillin
  2. Chloramphenicol
  3. Clarithromycin
  4. Doxycycline
  5. Trimethoprim
A

Amoxicillin

143
Q

A 44 y/o man needs Abx treatment for infection with a penicillinase-producing strain of S. aureus. What Abx is this organism likely to be resistant to?

  1. Benzylpenicillin
  2. Co-amoxiclav
  3. Flucloxacillin
  4. Piperacillin with tazobactam
  5. Vancomycin
A

Benzyl-pencillin

(note - flucloxacillin is penicillinase-resistant)

144
Q

A 54 y/o man has a history of severe anaphylactic reaction to penicillin. He now requires Abx for treatment of sepsis of unknown cause. What Abx is most likely to be safe in the context of a severe penicillin allergy?

  1. Cefotaxime
  2. Ciprofloxacin
  3. Co-amoxiclav
  4. Ertapenem
A

Ciprofloxacin

Yr 3 - Pharmacology (18 decks)

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