Term
What are examples of systemically used aminoglycosides? |
|
Definition
gentamicin
tobramycin
amikacin |
|
|
Term
What are examples of topically used aminoglycosides? |
|
Definition
|
|
Term
What is the activity of aminoglycosides? |
|
Definition
bactericidal, concentration dependent |
|
|
Term
What is the major use of aminoglycosides? |
|
Definition
major use for over 30 yrs of AG is g-aerobic bacilli |
|
|
Term
What can aminoglycosides be used synergistically with and what for? |
|
Definition
synergistic bactericidal combination of AG and beta-lactam or vancomycin (inhibition of cell wall synthesis permits increased entry of AG into cell)
used for enterococcal endocarditis (ineffective vs. VRE)
used for pseudomonas (AG plus antipseudomonal penicillin or ceftazidime) |
|
|
Term
What are AGs ineffective against? |
|
Definition
|
|
Term
AGs are the DOC for treatment of endocarditis caused by what two bacteria? |
|
Definition
E. faecalis and non-VRE E. faecium |
|
|
Term
What is the DOC to treat endocarditis caused by E. faecalis and non-VRE E. faecium |
|
Definition
penicillin G or ampicillin combined with gentamicin or streptomycin |
|
|
Term
Gentamicin is the most often used AG for synergism with penicillins vs what three bacteria? |
|
Definition
enterococci
streptococci
staphylococci |
|
|
Term
What is the major advantage of tobramycin? |
|
Definition
major advantage is activity (2-4 times as active) against some strains of P. aeruginosa that are resistant to gentamicin |
|
|
Term
What is the major use of amikacin? |
|
Definition
empiric therapy of nosocomial aerobic gram- bacillary infections where significant gentamicin resistance exists |
|
|
Term
Neomycin is used topically for minor soft tissue infections combined with what two drugs? |
|
Definition
|
|
Term
Why should topical preperations of neomycin be avoided? |
|
Definition
neomycin may be highly sensitizing and cause dermatological reactions |
|
|
Term
|
Definition
poor CSF entry even with inflammation; levels attained (20-25% of serum) are inadequate for meningitis |
|
|
Term
|
Definition
excreted entrirely through glomerular filtration
half life of 2-3 hr; greatly increased in renal disease and required dosing adjustment |
|
|
Term
|
Definition
individualization of dosing regimens is advised due to the low (narrow) therapeutic index |
|
|
Term
What is the most frequent cause of drug induced contact dermatitis? |
|
Definition
|
|
Term
What are the characteristics of ototoxicity caused by AGs? |
|
Definition
cochlear
vestibular
may be reversible if toxicity is mild, but extensive damage is usually irreversible |
|
|
Term
What are predisposing factor for ototoxicity of AGs? |
|
Definition
concurrent ototoxic drugs |
|
|
Term
Which AG is more likely to affect vestibular function? |
|
Definition
|
|
Term
What is usually assocatied with nephrotoxicity of AGs? |
|
Definition
elevated trough serum levels of AGs |
|
|
Term
Is renal impairment reversible? |
|
Definition
|
|
Term
What is a predisposing factor for nephrotoxicity when using AGs? |
|
Definition
concurrent nephrotoxic drugs |
|
|
Term
tobramycin solution for inhalation is indicated for... |
|
Definition
management of cystic fibrosis patients with P. aeruginosa infections |
|
|
Term
What are the two main sources of tetracyclines? |
|
Definition
|
|
Term
How are tetracyclines (esp doxycycline) classified? |
|
Definition
long acting, lipophilic, hepatic elimination, bid dosing |
|
|
Term
What are tetracyclines spectrum of activity? |
|
Definition
broad spectrum bacteriostatic |
|
|
Term
Tetracyclines have good activity against... |
|
Definition
good activity vs. unusual spp.
intracellular organisms (highly active vs. spirochetes, mycoplasma, chlamydia, and rickettsia) |
|
|
Term
What interaction can tetracyclines have that decreases their absorbance? |
|
Definition
Chelate with divalent and trivalent cations to form insoluble complexes which are not absorbed (dairy products, mineral and vitamin supplements, antacids, cathartics) |
|
|
Term
Food greatly reduces the availability execpt for what two drugs? |
|
Definition
|
|
Term
Describe tetracycline distribution into the CSF and placental barrier? |
|
Definition
Poor entry into CSF even in inflammation; not indicated for meningitis
Crosses placental barrier and undergoes permanent sequestration in newly forming bone and teeth |
|
|
Term
How is doxycycline eliminated? |
|
Definition
Active biliary excretion and enterohepatic circulation (reabsorption); doxycycline half life unchanged in renal disease |
|
|
Term
What tetracycline is used for acne vulgaris? |
|
Definition
oral tetracyclines, low-dose, long-term
used in chronic, severe cases of acne vulgaris
no serious toxicity since doses are low |
|
|
Term
What tetracycline is used in Lyme Disease (Borrelia burgdoferi)? |
|
Definition
doxycycline
DOC for tx of early stage of Lyme Disease |
|
|
Term
What is the DOC for relapsing fever (Borrelia recurrentis)? |
|
Definition
tetracycline or doxycycline |
|
|
Term
What is the DOC for urogenital infections caused by C. trachomatis? |
|
Definition
doxycycline is the DOC for STDs (like non-gonococcal urethritis) |
|
|
Term
For PID (salpingitis) what must you provide coverage for and with what drugs? |
|
Definition
Gonococcus (cephalosporin)
C. trachomatis (doxycycline) |
|
|
Term
What respiratory infection is doxycycline the DOC for? |
|
Definition
atypical pneumonias (Mycoplasma, Chlamydia); however in vitro activity of doxycyclines is less than that of the macrolides |
|
|
Term
What rickettsial infections is doxycycline the DOC for? |
|
Definition
Rocky mountain spotted fever
typhus |
|
|
Term
What tetracycline is the DOC for Vibrio infections and what are two example of vibrio infections? |
|
Definition
doxycycline
cholera, gastroenteritis |
|
|
Term
Tetracyclines are the DOC for anthrax (B. anthracis) - how are they used? |
|
Definition
treatment of inhalational anthrax
treatment of cutaneous anthrax
prophylaxis
|
|
|
Term
Demeclocycline is used for... |
|
Definition
management of syndrome of inappropriate antidiuretic hormone relases (SIADH) |
|
|
Term
Explain how tetracyclines are incorporated into bone and teeth and what this causes? |
|
Definition
Dose-dependent incorporation into growing teeth, producing a yellow brown discoloratoin of enamel and possible faulty enamel formation |
|
|
Term
Explain how tetracyclines can cause deposits in crown of anterior teeth? |
|
Definition
Crown formation complete by 6-7 years, high risk of permanent teeth discoloration when used in children less than 8 years (least likely to occur with doxycycline but should avoid all tetracyclines in children less than 8 years and in pregancy) |
|
|
Term
Tetracyclines can cause temporary cessation of bone growth or bone deformity so what does this mean? |
|
Definition
contraindicated in pregnant or nursing women or in children < 9 years |
|
|
Term
What tetracycline must be taken on an empty stomach? |
|
Definition
|
|
Term
What two tetracyclines must be taken with meals? |
|
Definition
doxycycline and minocycline |
|
|
Term
Doxycycline may necessitate administration with meals because... |
|
Definition
|
|
Term
What should not be given for at least 2 hrs after dosing? |
|
Definition
no antacids, bismuth subsalicylate, vitamins, or mineral supplemants |
|
|
Term
Should tetracyclines be taken with a full glass of water and be given at bedtime? |
|
Definition
take with a full glass of water, do not give at bedtime |
|
|
Term
|
Definition
no affected by the two major tetracycline resistance mechanisms (ribosomal binding site alteration, active efflux); considered bacteriostatic |
|
|
Term
What is tigecycline approved to treat? |
|
Definition
complicated skin/skin structure infections (MRSA), complicated intraadbdominal infections (anerobes), CAP |
|
|
Term
What are two common macrolides? |
|
Definition
azithromycin
erythromycin |
|
|
Term
Is erythromycin bacteriostatic or bactericidal? |
|
Definition
|
|
Term
What is erythromycin used to treat? |
|
Definition
gram + cocci: used as an alternative for penicillin allergic patients |
|
|
Term
What bacteria is erythromycin active against and what is it inactive against? |
|
Definition
active vs group A and B streptococci, S. viridans, and penicillin-sensitive S. pneumoniae
ineffective vs. enterococci
active vs C. diptheriae and Bordatella pertussis (whooping cough) |
|
|
Term
What intracellular organisms is erythromycin active against? |
|
Definition
Legionella pneumonphila, mycoplasmas (M. pneumoniae, U. urealyticum), chlamydiae (C. pneumoniae) |
|
|
Term
Azithromycin has superior activity versus what? |
|
Definition
Mycoplasma, Chlamydia, H. influenzae |
|
|
Term
Either azithromycin (A) or erythromycin (E) is the DOC for... |
|
Definition
-pneumonia caused by Chlamydia, Mycoplasma, or Legionella (A)
-whooping cough (Bordatella pertussis, E)
-diptheriae (C. diptheriae; E + antitoxin)
-PID due to C. trachomatis (A); cephalosporin or flouroquinolone for gonoccocal coverage |
|
|
Term
What is used to treat pneumonia caused by Chlamydia, Mycoplasma, or Legionella? |
|
Definition
|
|
Term
What is used to treat Bordatella pertussis (whooping cough)? |
|
Definition
|
|
Term
What is used to treat diptheriae (C. diptheriae) |
|
Definition
|
|
Term
What is used to treat PID due to C. trachomatis? |
|
Definition
azithromycin - cephalosporin or flouroquinolone for gonococcal coverage |
|
|
Term
What is used for prophylaxis for gonoccocal and chlamydial ophthalmia neonatorum |
|
Definition
erythromycin topical 5% ointment |
|
|
Term
What is erythromycin's active form (base) inactivated by? |
|
Definition
inactivated by acid, so use delayed release (enteric coated) tablets |
|
|
Term
Chemical modification of base (erythromycin)? |
|
Definition
ethylsuccinate ester
estolate |
|
|
Term
Best availability of erythromycin is when? |
|
Definition
when taken in fasting state, except for stearate which should be taken with meals |
|
|
Term
|
Definition
|
|
Term
|
Definition
new tablets may be taken without regard to meals
once daily dosing |
|
|
Term
|
Definition
|
|
Term
Describe some erythromycin GI side effects and why they exist: |
|
Definition
nausea, diarrhea, cramps; dose related effects attributed to agonist effects at motilin receptors |
|
|
Term
Describe the toxicity associated with estolate? |
|
Definition
cholestatic hepatitis (probably safe in children, estolate offers no therapeutic advantage and should be avoided in adults) |
|
|
Term
Macrolides and cardiac side effects? |
|
Definition
-may prolong the QT interval
-erythromycin has been associated with rare cases of torsades |
|
|
Term
Erythromycin and drug interactions? |
|
Definition
drug interactions due to inhibition of P450 system |
|
|
Term
Which macrolide has the least amount of P450 inhibition? |
|
Definition
|
|
Term
What is telithromycin used for? |
|
Definition
developed specifically for treatment of community-acquired respiratory tract infections caused by both common and atypical pathogens, including resistant strains |
|
|
Term
Telithromycin and resistance? |
|
Definition
Telithromycin is unaffected by resistance mechanisms used against macrolides |
|
|
Term
|
Definition
-strongly inhibits CYP3A4
-may prolong the QTc interval
-case reports of patients with jaundice, abnormal hepatic function, acute hepatic failure, and fulminant hepatitis leading to transplant or fatality |
|
|
Term
What type of bacteria does clindamycin treat? |
|
Definition
anaerobes (due to the association with pseudomembranous colitis, use of clindamycin is largely restricted to anaerobic infections) |
|
|
Term
What is clindamycin also used to treat? |
|
Definition
also used for mixed intraabdominal and female genital tract infections in combination with an AG |
|
|
Term
How is clindamycin prepared for use in acne? |
|
Definition
|
|
Term
Clindamycin and CSF distribution? |
|
Definition
poor entry into CSF (about 10% of serum levels); not indicated for meningitis |
|
|
Term
How is clindamycin used to treat anaerobic infections? |
|
Definition
alternate DOC for infections due to B. fragilis; alternative to penicillin G for other anaerobes |
|
|
Term
Clindamycin can also be used for anaerobic coverage for... |
|
Definition
mixed aerobic-anaerobic infections |
|
|
Term
Clindamycin can be used to treat two other things... |
|
Definition
bone and joint infections (staphylococcal or anaerobic osteomyelitis)
acne vulgaris (topical preperations) |
|
|
Term
Describe clindamycin antibiotic associated psedomembranous colitis (AAPMC) |
|
Definition
incidence estimated at 1.9 per 1000 courses of clindamycin (1.5 for cephalosporins, 2.1 for ampicillins); incidence of significant lincosamide-induced colitis ranges from 0.1-10% |
|
|
Term
What are the sxs of AAPMC? |
|
Definition
profuse, watery diarrhea (10-20 stools/d); blood and mucous may be present in the stool (5-10%), intestinal lesions produced are covered by a pseudomembrane |
|
|
Term
|
Definition
superinfection of bowel by C. dificile, and production of two extracellular toxins (enterotoxin and cytotoxin) which causes the colitis |
|
|
Term
What is the DOC for AAPMC? |
|
Definition
|
|
Term
What is the alternative agent for eradicating C. dificile? |
|
Definition
po vancomycin (reserve for cases not responsive to two courses of metronidazole or in life threatening colitis) |
|
|
Term
What drugs are contraindicated in the treatment of AAPMC? |
|
Definition
intestinal antimotility drugs |
|
|
Term
What bacteria are chloramphenicol used to treat? |
|
Definition
virtually all obligate anaerobes are suseptible (good activity vs Rickettsia spp.) |
|
|
Term
CSF penetration of chloramphenicol? |
|
Definition
CSF levels about 20-50% of plasma levels in the presence of uninflamed meninges, and about 45-90% of plasma levels in the presence of inflamed meninges; formerly used for empiric therapy of meningitis in combination with ampicillin
brain tissue levels about 9 times that of plasma - treat brain abcesses |
|
|
Term
Does chloramphenicol have a low or high TI? |
|
Definition
low TI; reserved only for serious infections for which less toxic agents are ineffective or contraindicated |
|
|
Term
Chloramphenicol is alternative DOC for: |
|
Definition
rickettsial infections in pregnancy or tetracycline allergy; for non-pregnant individuals > 8 yrs in the absence of allergy, doxycycline is the DOC for Rocky Mountain Spotted Fever |
|
|
Term
What drug is useful in the treatment of epiglottitis, septic arthritis, or osteomyelitis due to H. infuenzae in penicillin allergic patients? |
|
Definition
|
|
Term
What is the ADR of chloramphenicol? |
|
Definition
|
|
Term
The narrow TI can causes? |
|
Definition
-reversible bone marrow depression
-aplastic anemia
-"gray" syndrome in full-term neonates and premature infants |
|
|
Term
Describe the aplastic anemia associated with chloramphenicol... |
|
Definition
-pancytopenia with aplastic marrow
-idiosyncratic, neither dose nor duration related
-poor prognosis, high % fatalities; only tx is bone marrow transplant |
|
|
Term
Describe "gray" syndrome associated with chloramphenicol use... |
|
Definition
unaltered drug accumulates to toxic levels (deficient glucuronidation, low GFR), causing inhibition of mitochondrial oxidative phosphorylation
usually reversible is drug d/c at onset of sxs |
|
|
Term
What is the main affect of mupirocin? |
|
Definition
inhibits bacterial proteins synthesis |
|
|
Term
What are the dosage forms and uses of mupirocin? |
|
Definition
2% ointment for dermatologic use (not for ophthalmic use): indicated for topical tx of impetigo due to S. aureus, beta-hemolytic strep, and S. pyogenes
2% ointment for intranasal use: indicated for eradication of nasal colonization with methicillin-resistant S. aureus in adult patients and healthcare workers |
|
|
Term
What does Quinopristin/dalfopristin affect? |
|
Definition
combination is synergistic, affecting both the early (dalfopristin) and late (quinupristin) stages of proteins synthesis |
|
|
Term
What is Quinupristin/dalfopristin used to treat? |
|
Definition
serious or life threatening infections associated with vancomycin-resistant E. faecium bacteremia (VREF; bacteriostatic) |
|
|
Term
ADR of quinupristin/dalfopristin? |
|
Definition
administered by IV infusion; most frequent ADR is at the infusion site |
|
|
Term
DI of quinupristin/dalfopristin |
|
Definition
potent inhibitor of CYP3A4 |
|
|
Term
Linezolid approved indications? |
|
Definition
-VRE E. faecium including concurrent bacteremia
complicated skin/skin structure infections, including -diabetic foot infections, without concominant osteomyelitis
-CAP: PSSP, MSSA, DRSP
-preferred DOC for VISA and VRSA
-preferred DOC for PRSP pneumonia |
|
|
Term
|
Definition
thrombocytopenia
myelosuppression |
|
|
Term
|
Definition
-weak, reversible, nonselective MAOI
-potential DI with adrenergic and serotonergic agents
-interaction with tyramine containing foods may cause hypertension
-reports of serotonin syndrome with concurrent use of serotonergic agents |
|
|