Cephalosporins

Question 1

What adverse event occurs if cephalosporin dosage isn’t adjusted in the presence renal impairment?

Answer 1

Induction of seizure activity

Question 2

What are some clinical uses for cephalosporins?

Answer 2

Respiratory pathogens that cause acute otitis media, sinusitis, group A streptococcal pharyngitis, pneumonia, chronic bronchitis.

Also for UTI’s

Question 3

Describe how Cephalosporins absorbed through the GI?

Answer 3

Oral formulations are well-absorbed

Question 4

Is hepatic metabolism significant in cephalosporins?

Answer 4

No

Question 5

How are cephalosporins excreted?

Answer 5

Via the kidneys as unchanged drug

Question 6

Aside from renal toxicity, Cephalosporins can also cause:

Answer 6

Hematological/Coagulation abnormalities

Question 7

Are cephalosporin’s stable in the presence of penicillinase produced by S. aureus?

Answer 7

Yes

Question 8

What lab values signifies a renal dosing adjustment is needed for cephalosporins?

Answer 8

Recommended when GFR is less than 30mL/min

Question 9

What is the MOA of Cephalosporins?

Answer 9

Inhibit mucopeptide synthesis in the bacterial cell wall

Question 10

What are the first generation cephalosporins?

Answer 10

Cephalexin & Cefazolin

Question 11

Can oral cephalosporins be taken with food?

Answer 11

Yes. Food or milk is okay

Question 12

Staphylococcal skin infections often respond to which generation of cephalosporins?

Answer 12

First-generation (Cephalexin)

Question 13

Cephalosporin Monitoring

Answer 13

Renal function
Signs of allergic reaction
Liver function
Coagulation abnormalities

Question 14

Cephalosporin ADRs

Answer 14

Severe allergic reactions, including anaphylaxis

Clostridium difficile-associated diarrhea

Coagulation abnormalities

Seizure activity

Question 15

Who are at risk for coagulation abnormalities from cephalosporin admin?

Answer 15

those with impaired renal function, cancer, Vit K synthesis, Low Vit K stores, or malnutrition

Question 16

Are cephalosporins Bacteriostatic or Bactericidal?

Answer 16

Bactericidal

Question 17

Describe the use of cephalosporins in pregnancy:

Answer 17

Generally safe in pregnancy
Cross the placenta & are excreted in breast milk
Shorter half lives

Question 18

What are the most common mechanisms of resistance to cephalosporins?

Answer 18

Beta-lactamase production and altered target sites.

Question 19

Cefazolin Adsorption

Answer 19

Not absorbed in GI tract

Question 20

Cefazolin Distribution

Answer 20

Various tissues and body fluids, including skin, bones, joints, gallbladder, and bile

Protein binding 80%

Question 21

Cephalexin Distribution

Answer 21

Widely throughout body, bone, bile, synovial fluid, pleural fluid

10-15% bound to plasma proteins

Question 22

Second Generation Cephalosporin:

Answer 22

Cefuroxime

Question 23

What are unique considerations for Cefuroxime?

Answer 23

Interacts with H-2 blockers
Increased activity against H.Influenza

Question 24

What is unique about Cefuroxime PO:

Answer 24

Oral prodrug (cefuroxime axetil): absorbed well in GI tract, hydrolyzed to active form.

Question 25

What are the third generation cephalosporins?

Answer 25

Cefdinir Cefpodoxime Ceftriaxone (IM/IV)

Question 26

Ceftriaxone should be avoided in this population?

Answer 26

Neonates at risk for hyperbilirubenemia

Question 27

Ceftriaxone (IM) is the recommended treatment for which STI?

Answer 27

Gonorrhea

Question 28

What instructions should you give to the patient when taking PO Cefdinir?

Answer 28

Take 2 hours before or 2 hours after antacids that contain magnesium or aluminum. Same for iron supplements

Question 29

What are the major drug interactions with Cephalosporins?

Answer 29

Probenecid Loop diuretics Warfarin

Question 30

Do 3rd generation cephalosporins cross the BBB?

Answer 30

Yes, parenteral form is used to treat meningitis.

Question 31

What type of dosing is required when using cephalosporins?

Answer 31

Renal dosing

Question 32

Are cephalosporins bactericidal or bacteriostatic?

Answer 32

Bactericidal

Question 33

Which cephalosporin has good tissue penetration & is the drug of choice for surgical prophylaxis?

Answer 33

Cefazolin (1st generation)

Question 34

Describe this relationship:

Answer 34

1st generation are more effective against gram + coverage, less against gram -, & they have poor CSF penetration. As the generations increase, there is less gram + coverage, more gram -, & more CSF penetration

Question 35

What instruction should be given to patient when taking PO Cefpodoxime?

Answer 35

Should be taken with food to enhance absorption

Question 36

What is similar about Cepodoxime and Cefuroxoime?

Answer 36

Both prodrugs

Question 37

Cefpodoxime is the most active oral agent against:

Answer 37

N. Gonorrhea

Question 38

How is Ceftriaxone distributed?

Answer 38

Highly bound to protein

Question 39

Monitoring for Ceftriaxone includes:

Answer 39

hepatic dysfunction as it can extend half-life & excretion

Question 40

Ceftriaxone is contraindicated in:

Answer 40

Neonates younger than 28 days