Infections Flashcards
What is the spectrum of activity of natural PCNs?
Gram +
True of False:
Very little resistance has occurred to natural PCNs.
False
What class of drugs is used to treat MSSA? (Methicillin-sensitive Staph aureus)
Pencillin-resistant penicillins or anti-staphyloccal penicillins
Name the most commonly used anti-staph PCNs.
Methicillin
Nafcillin
What is the spectrum of coverage for aminopenicillins?
Gram + and Gram -
Name the most common aminopenicillin that is used IV.
Unasyn.
Why are beta-lactamase inhibitors sometimes added to aminopenicillins?
They protect the penicillins from inactivation by beta-lactamases.
Are anti-pseudomonal penicillins used more in the outpatient or inpatient setting?
Inpatient (ex: Zosyn)
What is the spectrum of coverage for anti-pseudomonal penicillins?
Gram + and -
What is the main adverse effects of beta-lactams?
GI (specifically diarrhea)
GI side effects of beta-lactams: do they increase or decrease with broader spectrum coverage?
The broader the coverage, the more likely the GI side effects.
What is the spectrum of coverage for each generation of cephalosporins?
1st: +
2nd: + and -
3rd: -
4th: + and -
5th: + and -
What are the most common first generation cephalosporins?
Keflex (cephalexin) and Ancef (cefazolin)
What setting are third generation cephalosporins mostly used in?
Inpatient
What are the two most commonly used IV preparations of 3rd generation cephalosporins?
Ceftriaxone (Rocephin)
Ceftazidime (Fortaz)
Which cephalosporin has good CNS penetration, making it a good choice in meningitis treatment?
Ceftriaxone (Rocephin)
What is the 4th generation cephalosporin?
Describe it’s spectrum of coverage and uses.
cefepime (Maxipime)
Gram + and -
IV
febrile neutropenia, peritonitis, HCAP
What is the 5th generation of cephalosporins unique coverage?
MRSA, but not psuedomonas
What is the primary adverse effect of cephalosporins?
GI upset
What do we generally see the carbapenems reserved for?
“Heavy hitters.”
Resistant infections.
What is the spectrum of coverage for carbapenems?
Broad
If a patient has a PCN allergy, is it safe to prescribe a cephalosporin?
Generally, yes.
True or false:
Judicious use of fluoroquinolones had led to resistance.
True
Which second generation fluoroquinolone has good pseudomonas coverage?
Ciprofloxacin
What are the two most common uses for levofloxacin?
UTI
URI
Which two fluoroquinolones are “respiratory”?
Levofloxacin
Moxifloxacin
What is the boxed warning for fluoroquinolones?
Tendon rupture.
What CNS adverse effects of fluoroquinolones are more prominent in the elderly?
Headache, dizziness, drowsiness
What setting are aminoglycosides generally used in?
Inpatient
What spectrum are aminoglycoside agents used for?
Gram -
Pharmacokinetic monitoring of aminoglycosides is used for what toxicities for peaks and troughs?
Peak: Efficacy and Ototoxicity
Troughs: Nephrotoxicity
Macrolides are commonly used for:
URI
H. Pylori
Erythromycin is no longer generally used to treat infection, but rather used for:
prokinetic properties in GI (diabetic gastroparesis)
What cardiac side effect of macrolides requires close monitoring?
QT prolongation
What type of bacteria is clindamycin most well-known for treating?
Anaerobic
What complication of clindamycin is most common?
C-diff
What is the mechanism of action of clindamycin?
Protein synthesis inhibitor
What is the spectrum of coverage for tetracyclines?
Broad
Why should tetracyclines be taken on an empty stomach?
They bind with cations.
Why are tetracyclines contraindicated in those under 8 years of age and in pregnancy/lactation?
Permanent yellow-brown staining of teeth.
True of false:
Vancomycin has good oral absorption.
False
What is oral vanco usually used for?
Cdiff
For Vanco, what are the peaks and troughs used for?
Peaks: toxicity (oto/nephro)
Troughs: Efficacy
Besides oto/nephro toxicity, what is the other common side effect of vanco?
“Red man” or “Red neck” Syndrome
Histamine release causing a flushed look
What is the most common sulfonamide drug used?
trimethoprim/sulfamethoxazole (Bactrim)
What is the mechanism of action of sulfonamides?
Inhibit bacterial growth by blocking folic acid synthesis.
For patients with sulfa allergy, what are some drugs/drug classes to use caution with?
Loop diuretics, thiazides, sulfonylureas, sumatriptan, topiramate.
What is a drug very commonly used to treat UTI?
Nitrofurantoin
What toxicity is known to Nitrofurantoin?
Neuropathy and lung toxicity
What drug can be used as one time dose for UTI?
Fosfomycin
Does flagyl have anaerobic coverage?
Yes
Why shouldn’t patients on Flagyl drink alcohol?
Disulfiram-like reaction.
What two medications are used in latent TB treatment?
Rifampin
Isoniazid
What is a known adverse effect of Rifampin?
Red secretions
What is side effects of Isoniazid?
Isolated nerve problems
