Cephalosporins Exam 1 Drug list Flashcards
Need to know Cephalosporins
First gen (Cephalexin and Cefazolin(IV/IM)
Second gen (Cefuroxime)
Third gen (Cefdinir, Cefpodoxime, Ceftriaxone (IM/IV))
Cephalosporins are similar to
Penicillin’s chemically and structurally
What adverse event occurs if cephalosporin dosage isn’t adjusted in the presence renal impairment?
Induction of seizure activity
Cephalosporins most effective against
Rapidly growing organisms forming cell walls when antibiotic concentrations exceed the pathogen’s MIC for at least 50% of the dosing interval
What are some clinical uses for cephalosporins
Active against respiratory pathogens
Acute otitis media, sinusitis, group A streptococcal pharyngitis, pneumonia, chronic bronchitis, and UTIs
how well are cephalosporins absorbed through the GI?
Oral formulations are well-absorbed
Is hepatic metabolism significant in cephalosporins?
No
How are cephalosporins excreted?
Via the kidneys as unchanged drug
Renal impairment significantly extends half-life
What species are intrinsically resistant to cephalosproins?
Enterococcus species
Are cephalosporin’s stable in the presence of penicillinase produced by S. aureus?
Yes
What lab values signifies a renal dosing adjustment is needed for cephalosporins?
Recommended when GFR is less than 30mL/min
Cephalosporins MOA
Inhibit mucopeptide synthesis in the bacterial cell wall
Make bacterium osmotically unstable
Cephalexin and Cefazolin are active against
Gram-positive cocci, S. aureus, s. epidermidis, and most streptococci
ex. E.coli, proteus mirabilis, klebsiella pneumoniae
Cephalexin and Cefazolin Common Side Effects
Gastrointestinal upset (nausea, vomiting, diarrhea)
Rash
Allergic reactions, including anaphylaxis (rare)
Staphylococcal skin infections often respond to which generation of cephalosporins?
First-generation (Cephalexin)
Cephalosporin Monitoring
Renal function especially in patients with renal impairment (BUN and CrCl)
Signs of allergic reaction, such as rash, itching, swelling, and respiratory difficulties
Periodic liver function tests during prolonged therapy (tiredness, weakness, and jaundice)