Term
| What cell wall inhibitor binds to the D-Ala-D-Ala terminus of nascent peptidoglycan pentapeptide? |
|
Definition
|
|
Term
| How is resistance created against Vancomycin? |
|
Definition
| Alteration in the peptapeptide binding site |
|
|
Term
| What spectrum does Vancomycin have? |
|
Definition
Narrow - primarily against G+
Staph aureus
S. epidermidis
Streptococcal endocarditis
Pseudomenbranous colitis |
|
|
Term
| What type of infections can Vancomycin be taken orally for? |
|
Definition
|
|
Term
| What antibiotic can cause ototoxicity with high concentration or rapid infusion? |
|
Definition
|
|
Term
| Risk of Nephrotoxicity increases with Vancomycin when co-administered with what drugs? |
|
Definition
aminoglycoside
cyclosporin
Amphotericin |
|
|
Term
| What drug has an adverse effect of "Red man syndrome"? What is the syndrome? |
|
Definition
Vancomycin
Histamine release, flushing, chills, fever
Vasodilation, low BP, patient collapse or shock |
|
|
Term
| What adverse effects occur in Myloma patients taking Vancomycin? |
|
Definition
| produce high IgA, binds and reduces vancomycin levels |
|
|
Term
| What are the 4 therapeutic uses of Vancomycin? |
|
Definition
Serious infection
(not sensitive to less toxic agents)
MRSA
(switch to nafcillin if sensitivity)
Enterococcus for PCN allergy
(may co-administer aminoglycoside)
Pseudomembranous colitis - C. difficile |
|
|
Term
| What antibiotics treat Enterococci? |
|
Definition
|
|
Term
| What protein synthesis inhibitor binds to 23S RNA on 50 ribosomal subunit? |
|
Definition
|
|
Term
| What organisms is Linezolid bacteriostatic against? Bacteriocidal against? |
|
Definition
Bacteriostatic - staphylocci and enterococci
Bacteriocidal - streptococci |
|
|
Term
| What are the FDA approved indications for Linezolid? |
|
Definition
Both Enterococcus faecium and faecalis
MRSA and MR epidermidis
PCN-resistant S. aureus
Reserved for serious VRE infections |
|
|
Term
| How can Linezolid be administered? |
|
Definition
Both oral and parenteral use
100% absorption of oral dose!! |
|
|
Term
| How does food affect the absorption of Linezolid? |
|
Definition
| Delays absorption, but not peak drug levels |
|
|
Term
| Why must the oral suspension of Linezolid be used with caution with phenylketonuria? |
|
Definition
|
|
Term
| Why can Linezolid cause Hypertension? |
|
Definition
| from increased absorption of tyramine from the diet |
|
|
Term
| What is the Tetracycline antibiotic? |
|
Definition
|
|
Term
| What is the general mechanism of action of the Tetracyclines? |
|
Definition
Inhibits Protein Synthesis by reversibly binding 30S ribosome
Bacteriostatic
Enters cells by passive diffusion through porin channels |
|
|
Term
| What spectrum of bugs do Tetracyclines work against? |
|
Definition
G+ and G- bacteria
(aerobic and anaerobic)
Mycoplasma
Chlamydia
Protozoa
Rickettsiae
Spirochetes |
|
|
Term
| Tetracycline may be the drug of choice for which organisms? |
|
Definition
Mycoplasma
Chlamydia
Rickettsiae
Spirochetes |
|
|
Term
| How does resistance occur to Tetracyclines? |
|
Definition
Occurs Slowly
Reduced transport of drug
Increased efflux from cell
Resistance to 1 Tetracycline provides resistance to All |
|
|
Term
| What inhibits Tetracyclines Absorption? How is it absorbed best? |
|
Definition
Inhibited by di- and trivalent cations
(Ca++, Mg++, Fe+++, Al+++)
Absorbed best in acidic stomach - no antacids |
|
|
Term
| Where do tetracyclines concentrate in the body? |
|
Definition
Liver
Kidney
Spleen
Tumors
Bone and Teeth when undergoing calcification |
|
|
Term
| How are the tetracyclines metabolised and excreted? |
|
Definition
|
|
Term
| How are the tetracyclines primarily excreted? |
|
Definition
|
|
Term
| What adverse effects can occur in the GI from Tetracyclines? |
|
Definition
Nausea, Vomiting, diarrhea
Avitaminosis
Superinfections
(changes in microbial flora can lead to candidiasis) |
|
|
Term
| What Tetracycline is least likely to cause superinfection problems? why? |
|
Definition
Doxycycline
Its more cmopletely absorbed so doesn't disrupt the microbial flora |
|
|
Term
| Why should tetracyclines be avoided during gestation or to children <8 years old? |
|
Definition
Chelation of Ca++
causes discoloration of teeth
Depression of bone Growth |
|
|
Term
| What tetracyline causes photosensitivity most frequently? |
|
Definition
|
|
Term
| What are the therapeutic uses of Tetracyclines? |
|
Definition
Lyme Disease (Borrelia Burgdorferi)
Rickettsia infection
Chlamydia
Mycoplasma
Certain types of periodontal disease
Acne |
|
|
Term
| What are the Macrolides/Ketolides? |
|
Definition
Erythromycin
Clarithromycin
Azitromycin |
|
|
Term
| What is the Bacteriostatic action of Erythromycin? |
|
Definition
| Binds reversibly to 50S ribosomal subunit and inhibits protein synthesis |
|
|
Term
| Why is it important to maintain Erythromycin concentrations above MIC and insure patient compliance? |
|
Definition
Bacterial resistance develops rapidly
Plasmid mediated
Decreased transport
Modification of ribosomal target by methylases
Hydrolysis or drug by esterases |
|
|
Term
| Where does Erythromycin concentrate in the body and how is it excreted? |
|
Definition
Concentrates in Liver
(not metabolized)
Excreted primarily in bile and feces |
|
|
Term
| What is the 2nd choice after Penicillin G for G+ infections? |
|
Definition
|
|
Term
| What G+ infections is Erythromycin indicated for? |
|
Definition
Pneumoccocci or Group A Strep in PCN allergic patients
Listeria monocytogenes
Corynebacterium dephtheriae
Lyme Disease
**Used in Patients allergic to PCN** |
|
|
Term
| What G- infections is Erythromycin used for? |
|
Definition
Legionnaire's Disease
Mycoplasma pneumoniae infections
Some chlamydia infections |
|
|
Term
| What is the drug of choice for Legionnaire's disease? |
|
Definition
|
|
Term
| What is Chloestatic hepatitis associated with? |
|
Definition
|
|
Term
| What P450 interactions does Erythromycin have? |
|
Definition
Inhibits CYP450 enzyme
Increases concentrations of theophylline, warfarin, terfenadine, astemizole, carbamazepine, cyclosporine |
|
|
Term
| How does Clarithromycin compare with Erythromycin? |
|
Definition
More acid stable than erythromycin
Oral dose Increases with food
Rapid First Pass metabolism
Eliminated by kidney and liver |
|
|
Term
| What therapeutic uses does Clarithromycin have increased activity with? |
|
Definition
H. influenzae
Legionella pneumophila
Strep. Pneumoniae, S. pyogenes
Helicobacter pylori
Mycobacterium avium complex (DOC)
Chlamydia trachomatis
Moraxella catarrhalis |
|
|
Term
| What is the drug of choice for Mycobacterium avium complex? |
|
Definition
|
|
Term
How are the Macrolids ordered by t1/2?
(erythromycin, clarithromycin, azithromycin) |
|
Definition
Azithromycin - 35-40 hrs
Clarithromycin - 4 hrs
Erythromycin - 1.6 hrs |
|
|
Term
| How is Clarithromycins absorption dose effected by food? How is Azithromycin's? |
|
Definition
Clarithromycins - Increased
Azithromycin - Decreased |
|
|
Term
| What macrolid concentrates in neutrophils, macrophages, and fibroblasts? |
|
Definition
|
|
Term
| How is Azithromycin excreted? |
|
Definition
|
|
Term
| What macrolid is similar in effectiveness to penicillin V for pharyngitis and amoxicillin for sinusitis? |
|
Definition
|
|
Term
| What is the drug of choice for Campylobacter, Legionella, and Mycobacterium avium complex? |
|
Definition
|
|
Term
| What is the mechanism of Clindamycin? |
|
Definition
Inhibits protein synthesis
Binds to 50S subunit of ribosome |
|
|
Term
| What is Clindamycin effective for? How does resistance develop? |
|
Definition
Effective for anaerobes
(G+ organisms)
Resistance occurs slowly - stepwise
decreased affinity of drug for ribosome |
|
|
Term
| What antibiotic can penetrate bone but does not penetrate to CSF? |
|
Definition
|
|
Term
| What antibiotic that binds 50S subunit can cause Pseudomembranous colitis? |
|
Definition
Clindamycin
(from Clostridium difficile) |
|
|
Term
| What are the therapeutic uses for Clindamycin? |
|
Definition
Bacteroides fragilis (outside CNS)
Prophylacsis for PCN allergic
Toxoplasmosis in AIDS- with pyrimethamine
Pneumocystis jiroveci pneumonia - with primaquine |
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