Handbook of Antimicrobial Therapy

242 Pages·2008·0.95 MB·English

by  Medical Letter

Handbook of
Antimicrobial
Therapy
Selected Articles fromTreatment Guidelines
with updates fromThe Medical Letter®
Published by
The Medical Letter, Inc.
1000 Main Street
New Rochelle, New York 10801-7537
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Fax [phone]
www.medicalletter.org
18th Edition
Contents
Summary................................................................................................. 1
Pathogens in Specific Organs and Tissues........................................... 25
Bacterial Infections
Choice of Antibacterial Drugs.......................................................... 37
Clostridium difficile-Associated Disease (CDAD).......................... 86
Community-Acquired Bacterial Pneumonia.................................... 92
Copyright 2008
Doripenem (Doribax)....................................................................... 98
(ISSN 0190-3454)
(ISBN 0-9719093-8-5) Tuberculosis........................................................................................ 103
The Medical Letter Inc. A Blood Test for Tuberculosis......................................................... 122
1000 Main Street Antimicrobial Prophylaxis for Surgery........................................... 125
New Rochelle, New York 10801-7537 Major Changes in Endocarditis Prophylaxis Prophylaxis for
Dental, GI and GU Procedures...................................................... 140
Fungal Infections.................................................................................... 143
HIV Infection.......................................................................................... 165
No part of the material may be reproduced or transmitted by any process in Two New Drugs for HIV Infection..................................................... 191
whole or in part without prior permission in writing. The editors and Viral Infections (Non-HIV)................................................................... 197
publisher do not warrant that all the material in this publication is accurate
Parasitic Infections................................................................................. 225
and complete in every respect. The editors and publisher shall not be held
Sexually Transmitted Infections........................................................... 281
responsible for any damage resulting from any error, inaccuracy or omission.
Immunization (Adult)............................................................................ 303
Permissions: To reproduce any portion of this issue, please e-mail your Herpes Zoster Vaccine (Zostavax)....................................................... 323
request to [email protected] Human Papillomavirus........................................................................ 326
Mumps Outbreak Recommendations.................................................. 329
Second Dose of Varicella Vaccine....................................................... 331
Tdap, DTaP Mix-Ups.......................................................................... 333
VariZIGfor Prophylaxis After Exposure to Varicella......................... 335
Advice for Travelers............................................................................... 339
Adverse Effects of Antimicrobial Drugs................................................ 365
Pregnancy, Safety in................................................................................381
Trade Names........................................................................................... 395
Dosage of Antimicrobial Drugs............................................................... 417
Index........................................................................................................ 449
Table Index.......................................................................................... 474
EDITOR
Mark Abramowicz, M.D. Introduction
EXECUTIVE EDITOR
Gianna Zuccotti, M.D., M.P.H., Weill Medical College of Cornell University
The Medical Letter, Inc. is a nonprofit company founded in 1958 by
DEPUTY EDITOR
Arthur Kallet, the co-founder of Consumers Union, and Dr. Harold
Jean-Marie Pflomm, Pharm.D.
Aaron, with the goal of providing healthcare professionals with objective,
ASSISTANT EDITOR, DRUG INFORMATION independent analyses of both prescription and over-the-counter drugs. In
Susan Morey, Pharm.D. addition to its newsletters, The Medical Letter on Drugs and
Therapeutics and Treatment Guidelines from The Medical Letter, the
CONTRIBUTING EDITOR
company also publishes handbooks and software on topics such as
Eric J. Epstein, M.D., Albert Einstein College of Medicine
adverse drug interactions and antimicrobial therapy. It is supported solely
SENIOR ASSOCIATE EDITORS by subscription fees and accepts no advertising, grants or donations.
Donna Goodstein
Amy Faucard The Medical Letter on Drugs and Therapeutics offers comprehensive
drug evaluations of virtually all new drugs and reviews of older drugs
ASSOCIATE EDITOR
when important new information becomes available on their usefulness
Cynthia Macapagal Covey
or adverse effects. Occasionally, The Medical Letterpublishes an article
EDITORIAL ASSISTANT on a new non-drug treatment or a diagnostic aid. Treatment Guidelines
Liz Donohue from The Medical Letterconsists of review articles of drug classes for
treatment of major indications. A typical issue contains recommenda-
PRODUCTION COORDINATOR
tions for first choice and alternative drugs with assessments of the drugs’
Cheryl Brown
effectiveness, safety and cost. The Medical Letter is published every
MANAGINGEDITOR other week and Treatment Guidelinesis published once a month. Both
Susie Wong are intended to meet the needs of the busy healthcare professional who
wants unbiased, reliable and timely information on new drugs and com-
ADVISORY BOARD
prehensive reviews of treatments of choice for major indications. Both
Jules Hirsch, M.D., Rockefeller University
David N. Juurlink, BPhm, M.D., PhD, Sunnybrook Health Sciences Centre publications help healthcare professionals make decisions based on the
Richard B. Kim, M.D., Vanderbilt School of Medicine best interests of their patients, rather than the commercial interests of the
Gerald L. Mandell, M.D., University of Virginia School of Medicine pharmaceutical industry.
Hans Meinertz, M.D., University Hospital, Copenhagen
Dan M. Roden, M.D., Vanderbilt School of Medicine
F. Estelle R. Simons, M.D.,University of Manitoba
Neal H. Steigbigel, M.D.,New York University School of Medicine
VICE PRESIDENT & PUBLISHER
Yosef Wissner-Levy
Antibacterial Drugs: A Brief Summary for Quick Reference
The editorial process used for Medical Letter publications relies on a con- ANTIBACTERIAL DRUGS:
sensus of experts to develop prescribing recommendations. An expert con- A BRIEF SUMMARY FOR QUICK REFERENCE
sultant or one of our editors prepares the preliminary report on a drug (for
The Medical Letter) or drugs for particular indications (for Treatment AMINOGLYCOSIDES — Aminoglycosides are effective against
Guidelines) in terms of their effectiveness, adverse effects and possible many gram-negative bacteria, but not gram-positives or anaerobes. They
alternatives. Both published and available unpublished studies are care- are often used together with a ß-lactam antibiotic such as ampicillin,
fully examined, paying special attention to the results of controlled clin- ticarcillin, piperacillin, a cephalosporin, imipenem or aztreonam. They
ical trials. The preliminary draft is sent to members of the Advisory may be ototoxic and nephrotoxic, especially in patients with diminished
Board of The Medical Letter, consultants who have clinical and experi- renal function.
mental experience with the drug or type of drug or disease under review,
the FDA and sometimes the CDC. The article is edited in-house by our Amikacin (Amikin) —Amikacin is often effective for treatment of
editorial staff and the final publication is considered a crucial resource infections caused by gram-negative strains resistant to gentamicin and
for members of the healthcare community to consult when they are tobramycin, including some strains of Pseudomonas aeruginosa and
overwhelmed by advertisements and personal visits from sales represen- Acinetobacter. It is generally reserved for treatment of serious infections
tatives of the pharmaceutical industry. caused by amikacin-susceptible gram-negative bacteria known or sus-
pected to be resistant to the other aminoglycosides. Like other aminogly-
The Medical Letter, Inc., is based in New Rochelle, NY. For more infor-
cosides, its distribution to the lungs is limited and when used to treat
mation call [phone] or go to www.medicalletter.org.
gram-negative bacilli that cause pneumonia it should be combined with
another agent to which the organism is susceptible, such as a ß-lactam. It
has also been used concurrently with other drugs for treatment of some
mycobacterial infections.
Gentamicin (Garamycin, and others) — Useful for treatment of
many hospital-acquired infections caused by gram-negative bacteria.
Strains of gram-negative bacilli resistant to gentamicin are often suscep-
tible to amikacin or to one of the third-generation cephalosporins,
cefepime, or imipenem or meropenem. Gentamicin is also used with
penicillin G, ampicillin or vancomycin for treatment of endocarditis
caused by susceptible enterococci.
Kanamycin (Kantrex, and others) — Active against some gram-
negative bacilli (except Pseudomonas or anaerobes), but most centers
now use gentamicin, tobramycin or amikacin instead. Kanamycin can be
useful concurrently with other drugs for treatment of tuberculosis.
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Antibacterial Drugs: A Brief Summary for Quick Reference Antibacterial Drugs: A Brief Summary for Quick Reference
Neomycin— A drug that can cause severe damage to hearing and AZITHROMYCIN (Zithromax, and others)— See Macrolides
renal function and has the same antibacterial spectrum as kanamycin.
Parenteral formulations have no rational use because of their toxicity. AZTREONAM (Azactam) — A parenteral monobactam (ß-lactam)
Deafness has also followed topical use over large areas of skin, injection antibiotic active against most aerobic gram-negative bacilli, including
into cavities such as joints, and oral administration, especially in patients Pseudomonas aeruginosa, but not against gram-positive organisms or
with renal insufficiency. anaerobes. Aztreonam has little cross-allergenicity with penicillins and
cephalosporins.
Streptomycin — Streptomycin has been displaced by gentamicin
for treatment of gram-negative infections, but it is still sometimes used BACITRACIN — A nephrotoxic drug used in the past to treat severe
concurrently with other drugs for treatment of tuberculosis and is occa- systemic infections caused by staphylococci resistant to penicillin G. Its
sionally used with penicillin, ampicillin or vancomycin to treat entero- use is now restricted mainly to topical application.
coccal endocarditis.
CAPREOMYCIN (Capastat) — A second-line antituberculosis drug.
Tobramycin (Nebcin, and others) — Similar to gentamicin but
with greater activity in vitro against Pseudomonas aeruginosa and less CARBAPENEMS
activity against Serratia. In clinical use, it is not certain that it is signifi- Imipenem/Cilastatin (Primaxin) — The first carbapenem,
cantly less nephrotoxic than gentamicin. imipenem, has an especially broad antibacterial spectrum. Cilastatin
sodium inhibits renal tubular metabolism of imipenem. This combina-
AMINOSALICYLIC ACID (PAS) — Used in antituberculosis regi- tion may be especially useful for treatment of serious infections in which
mens for many years, its distressing gastrointestinal effects caused many aerobic gram-negative bacilli, anaerobes, and Staphylococcus aureus
patients to stop taking it prematurely. An enteric-coated oral formulation (but not oxacillin-resistant strains) might all be involved. It is active
(Paser) is more tolerable, and is used occasionally in combination with against many gram-negative bacilli that are resistant to third- and fourth-
other drugs in treating tuberculosis due to organisms resistant to first- generation cephalosporins, aztreonam and aminoglycosides. Resistance
line drugs. to imipenem in Pseudomonas aeruginosa occasionally develops during
therapy. It has been rarely associated with seizures particularly with high
AMOXICILLIN(Amoxil, and others) — See Penicillins doses in elderly patients.
AMOXICILLIN/CLAVULANIC ACID (Augmentin, and others) — Meropenem (Merrem) —A carbapenem for parenteral use similar
See Penicillins to imipenem/cilastatin. It may have less potential than imipenem for
causing seizures.
AMPICILLIN(Principen, and others) — See Penicillins
Doripenem (Doribax) — Doripenem has a spectrum of activity
AMPICILLIN /SULBACTAM(Unasyn) — See Penicillins similar to imipenem/cilastatin. In vitro, it is more active than imipenem
and meropenem against P. aeruginosa and is active against some
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Antibacterial Drugs: A Brief Summary for Quick Reference Antibacterial Drugs: A Brief Summary for Quick Reference
pseudomonal isolates resistant to the other carbapenems; the clinical sig- The second-generation cephalosporins have broader in vitro activity
nificance of this in vitroactivity is unknown. It may have less potential against gram-negative bacteria. Cefamandole (Mandol) has increased
than imipenem for causing seizures. activity against Haemophilus influenzae and some gram-negative bacilli,
but is occasionally associated with prothrombin deficiency and bleeding.
Ertapenem (Invanz) — Ertapenem has a longer half-life but nar- Cefoxitin (Mefoxin) has improved activity against Bacteroides fragilis,
rower antibacterial spectrum than imipenem, meropenem and doripenem. Neisseria gonorrhoeae and some aerobic gram-negative bacilli.
It is more active against some extended-spectrum ß-lactamase-producing Cefotetan (Cefotan) has a spectrum of activity similar to that of cefox-
gram-negative bacilli, but less active against gram-positive cocci, itin; it has a side chain that has rarely been associated with prothrombin
Pseudomonas aeruginosa and Acinetobacter spp. For empiric treatment deficiency and bleeding. Cefuroxime (Zinacef, Kefurox), another second-
of intra-abdominal, pelvic and urinary tract infections and community- generation cephalosporin, has a spectrum of activity similar to cefaman-
acquired pneumonia, it offers no advantage over older drugs other than dole. Cefuroxime and cefamandole are less active than third-generation
once-daily dosing. cephalosporins against penicillin-resistant strains of Streptococcus pneu-
moniae. Cefonicid (Monocid) has a longer half-life than the other sec-
CARBENICILLIN — See Penicillins ond-generation cephalosporins, but is less active against gram-positive
organisms and less active than cefoxitin against anaerobes.
CEPHALOSPORINS — All cephalosporins except ceftazidime have
good activity against most gram-positive cocci, and all cephalosporins are The third-generation cephalosporins, cefotaxime (Claforan), cefop-
active against many strains of gram-negative bacilli. All cephalosporins erazone (Cefobid), ceftizoxime (Cefizox), ceftriaxone (Rocephin) and
are inactive against enterococci and oxacillin-resistant staphylococci. ceftazidime (Fortaz, and others), and the fourth-generation cephalosporin,
These drugs are often prescribed for patients allergic to penicillin, but cefepime (Maxipime), are more active than the second-generation
such patients may also have allergic reactions to cephalosporins. Rare, cephalosporins against enteric gram-negative bacilli, including nosocomi-
potentially fatal immune-mediated hemolysis has been reported, particu- ally acquired strains resistant to multiple antibiotics. These agents are
larly with ceftriaxone and cefotetan. highly active against Haemophilus influenzae and Neisseria gonorrhoeae,
including penicillinase-producing strains. Except for ceftazidime, they are
The cephalosporins can be classified into four ‘‘generations’’based on moderately active against anaerobes, but often less so than metronidazole,
their activity against gram-negative organisms. All first-generation drugs chloramphenicol, clindamycin, cefoxitin, cefotetan, ampicillin/sulbac-
have a similar spectrum, including many gram-positive cocci (but not tram, piperacillin/tazobactam, ticarcillin/clavulanic acid, or carbapenems.
enterococci or oxacillin-resistant Staphylococcus aureus), Escherichia Ceftazidime has poor activity against gram-positive organisms and anaer-
coli, Klebsiella pneumoniae, and Proteus mirabilis. Among the first- obes. Cefotaxime, ceftizoxime, ceftriaxone and cefepime are the most
generation parenteral cephalosporins, cefazolin (Ancef, and others) is active in vitro against gram-positive organisms, but ceftizoxime has poor
less painful on intramuscular injection than cephapirin (Cefadyl, and activity against Streptococcus pneumoniae that are intermediate or highly
others). The first-generation parenteral cephalosporins are usually given resistant to penicillin. Cefoperazone, which can cause bleeding, is less
intravenously, and cefazolin is most frequently used because of its active than other third-generation cephalosporins against many gram-
longer half-life. negative bacilli, but more active than cefotaxime, ceftizoxime or ceftriax-
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Antibacterial Drugs: A Brief Summary for Quick Reference Antibacterial Drugs: A Brief Summary for Quick Reference
one against Pseudomonas aeruginosa. Ceftazidime and cefepime have the lococci. Ceftibuten (Cedax) is an oral cephalosporin similar to cefixime
greatest activity among the cephalosporins against Pseudomonas aerugi- in its gram-negative activity and poor activity against staphylococci, but
nosa. Cefepime has somewhat greater activity against enteric gram-nega- it has only inconsistent activity against Streptococcus pneumoniae.
tive bacilli than the third-generation cephalosporins. The third-generation
cephalosporins and cefepime are expensive, but are useful for treatment of Ceftobiprole is an investigational broad-spectrum cephalosporin with
serious hospital-associated gram-negative infections when used alone or in activity against MRSA. It may soon be available.
combination with aminoglycosides such as gentamicin, tobramycin or
amikacin. Gram-negative bacteria that produce “broad spectrum” ß-lacta- CHLORAMPHENICOL (Chloromycetin, and others) — An effective
mases are resistant to first-generation cephalosporins, but are usually sen- drug for treatment of meningitis, epiglottitis, or other serious infections
sitive to second and third generation cephalosporins. However, caused by Haemophilus influenzae, severe infections with Salmonella
gram-negative bacilli that produce “extended spectrum ß-lactamases”, par- typhi, for some severe infections caused by Bacteroides (especially those
ticularly some Klebsiella strains and those that produce chromosomally- in the central nervous system), and for treatment of vancomycin-resistant
encoded ß-lactamases, are usually resistant to first, second and Enterococcus. Chloramphenicol is often an effective alternative for treat-
third-generation cephalosporins. These organisms are often hospital-asso- ment of pneumococcal or meningococcal meningitis in patients allergic
ciated. Cefipime may be more active than the third-generation to penicillin, but some strains of Streptococcus pneumoniae are resistant
cephalosporin against these strains, but imipenem and meropenem are to it. Because it can cause fatal blood dyscrasias, chloramphenicol
most consistently active against them. Cefotaxime and ceftriaxone are should be used only for serious infections caused by susceptible bacteria
often used for treatment of meningitis. Ceftriaxone has been widely used that cannot be treated effectively with less toxic agents.
for single-dose treatment of gonorrhea.
CINOXACIN (Cinobac, and others) — See Quinolones
Cephalexin (Keflex, and others), cephradine (Velosef, and others),
and cefadroxil (Duricef, and others) are well-absorbed oral CIPROFLOXACIN (Cipro, and others)— See Fluoroquinolones
cephalosporins with first-generation antimicrobial activity; cephradine is
also available for parenteral use. Cefaclor (Ceclor, and others), cefurox- CLARITHROMYCIN (Biaxin, and others)— See Macrolides
ime axetil (Ceftin), cefprozil (Cefzil) and loracarbef (Lorabid) are oral
second-generation agents with increased activity against Haemophilus CLINDAMYCIN (Cleocin, and others) — A derivative of lincomycin
influenzae and Moraxella catarrhalis. Cefixime (Suprax), an oral with a similar antibacterial spectrum, clindamycin can cause severe diar-
cephalosporin with activity against gram-positive organisms similar to rhea and pseudomembranous colitis. It is one of the alternative drugs for
that of first-generation cephalosporins except for its poor activity against anaerobic infections outside the central nervous system, and can also be
staphylococci; against gram-negative bacteria, it has greater activity than used as an alternative for treatment of some staphylococcal infections in
second-generation cephalosporins. It is useful for single-dose oral treat- patients allergic to penicillins. Strains of S. aureusthat are sensitive to
ment of gonorrhea. Cefpodoxime proxetil (Vantin), cefdinir (Omnicef) clindamycin, but resistant to erythromycin become rapidly resistant to
and cefditoren pivoxil (Spectracef) are oral cephalosporins similar to clindamycin when it is used. Clindamycin is also used concurrently with
cefixime, but with greater activity against methicillin-susceptible staphy- other drugs to treat Pneumocystis carinii pneumonia and toxoplasmosis.
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Antibacterial Drugs: A Brief Summary for Quick Reference Antibacterial Drugs: A Brief Summary for Quick Reference
Clindamycin may be beneficial in treatment of necrotizing fasciitis due DEMECLOCYCLINE (Declomycin) — See Tetracyclines
to Group A streptococcus but, because of the possibility of resistance to
clindamycin, it should be used in combination with penicillin G. DICLOXACILLIN (Dycill, and others) — See Penicillinase-resistant
Penicillins
CLOFAZIMINE (Lamprene) — An oral agent used with other drugs
for treatment of leprosy. DIRITHROMYCIN (Dynabac) — See Macrolides
CLOXACILLIN — See Penicillinase-resistant Penicillins DORIPENEM(Doribax)— See Carbapenems
COLISTIMETHATE (Coly-Mycin) — See Polymyxins DOXYCYCLINE (Vibramycin, and others) — See Tetracyclines
CYCLOSERINE (Seromycin, and others) — A second-line antituber- ERTAPENEM (Invanz) — See Carbapenems
culosis drug.
ERYTHROMYCIN (Erythrocin, and others) — See Macrolides
DAPTOMYCIN (Cubicin) — A cyclic lipopeptide antibiotic that is
effective for treating complicated skin and soft tissue infections and ERYTHROMYCIN-SULFISOXAZOLE (Pediazole, and others) —
methicillin-sensitive and methicillin-resistant S. aureus bacteremia, See Macrolides
including right-sided endocarditis. It is rapidly bactericidal against gram-
positive bacteria by causing membrane depolarization. Its anti-bacterial ETHIONAMIDE (Trecator-SC) — A second-line antituberculosis
activity includes oxacillin-sensitive and resistant, and vancomycin-sensi- drug.
tive and resistant S. aureusand coagulase-negative staphylococci, strepto-
cocci and vancomycin-sensitive and resistant enterococci. Rarely, S. ETHAMBUTOL (Myambutol) — Often used in antituberculosis regi-
aureus strains with decreased susceptibility to daptomycin have emerged mens, it can cause optic neuritis.
during treatment of S. aureus endocarditis with daptomycin. Some strains
of S. aureus that have emerged with reduced susceptibility to vancomycin FLUOROQUINOLONES —Fluoroquinolones are synthetic anti-bac-
during treament with vancomycin, have shown reduced susceptibility to terial agents with activity against gram-positive and gram-negative
daptomycin. It is administered intravenously once daily and is excreted organisms. With the increased use of fluoroquinolones, resistant organ-
unchanged in urine; dose adjustments are required when given to individ- isms have become more frequent, especially among strains of
uals with severe renal insufficiency. Adverse effects include the potential Staphylococcus aureus and Pseudomonas aeruginosa. Resistance
for skeletal muscle damage, with rare reversible CPK elevations. More among Streptococcus pneumoniae strains has begun to emerge but is still
severe muscle effects, which were seen in preclinical studies, do not seem rare, especially in the US. None of these agents is recommended for use
to occur at the currently approved doses; higher doses may increase the in children or pregnant women. All can cause gastrointestinal distur-
potential for rhabdomyolysis. Daptomycin should not be used to treat bances and, less commonly central nervous system toxicity. Tendon
pneumonia because it is inactivated by surfactant. effects and hypersensitivity reactions, including vasculitis, serum sick-
8 9
Antibacterial Drugs: A Brief Summary for Quick Reference Antibacterial Drugs: A Brief Summary for Quick Reference
ness-like reactions and anaphylaxis, occur rarely. Hypo- and hyper- increasing. Levofloxacin, moxifloxacin, ofloxacin or ciprofloxacin are
glycemia can also occur rarely. sometimes used as second-line anti-tuberculous drugs in combination with
other agents. Moxifloxacin has been used more frequently for treatment of
Ciprofloxacin (Cipro, and others)—Used for oral or intravenous tuberculosis than the other fluoroquinolones. Levofloxacin is more effec-
treatment of a wide variety of gram-positive and gram-negative bacterial tive for treatment of Legionella pneumophilathan azithromycin. The use
infections in adults, including those due to oxacillin-susceptible and of fluoroquinolones has been associated with the recent increase in severe
resistant staphylococci, Haemophilus influenzae, Neisseria, enteric cases of C. difficile colitis. Levofloxacin and moxifloxacin are available
pathogens and other aerobic gram-negative bacilli, and Pseudomonas for both oral and parenteral use. Gemifloxacin is only available for oral
aeruginosa, but not anaerobes. Newer fluoroquinolones such as lev- use. Levofloxacin and moxifloxacin have rarely been associated with tor-
ofloxacin, gatifloxacin, gemifloxacin and moxifloxacin are preferred for sades de pointes arrhythmia. Gemifloxacin has produced more rashes than
treatment of gram-positive coccal infections such as those caused by S. other fluoroquinolones.
pneumoniaeand S. aureus. Ciprofloxacin is useful for treatment of uri-
nary tract infections caused by enteric gram-negative bacilli or Gatifloxacin — Gatifloxacin has been associated with hypergyl-
Pseudomonas aeruginosa. Oral ciprofloxacin has been effective in treat- cemia and hypoglycemia more often than the other fluoroquinolones and
ing patients with neutropenia and fever who are at low risk for mortality. it is no longer available.
Ciprofloxacin is now one of the preferred prophylactic agents for con-
tacts of patients with meningococcal disease. It is also used for prophy- Lomefloxacin (Maxaquin) — An oral once-a-day fluoroquinolone
laxis after Bacillus anthracis (Anthrax) exposure. Emergence of promoted for treatment of urinary tract infections and bronchitis, but
resistance in staphylococcal and Pseudomonas strains and other gram- pneumococci and other streptococci are resistant to the drug.
negative organisms is increasingly encountered.
Norfloxacin (Noroxin) — An oral fluoroquinolone for treatment of
Levofloxacin (Levaquin), moxifloxacin (Avelox) and gemifloxacin urinary tract infections due to Enterobacteriaceae, Enterococcus or
(Factive) —More active than ciprofloxacin or ofloxacin against gram- Pseudomonas aeruginosa.
positive organisms, such as Streptococcus pneumoniae, including strains
highly resistant to penicillin, and Staphylococcus aureus. Like other flu- Ofloxacin (Floxin, and others)— An oral and intravenous fluoro-
oroquinolones, they are active against Legionella pneumophila, quinolone similar to ciprofloxacin but less active against Pseudomonas.
Chlamydia spp., Mycoplasma pneumoniae, Haemophilus influenzae and Ofloxacin can be used for single-dose treatment of gonorrhea and for
Moraxella catarrhalis. All are effective for many community-acquired seven-day treatment of chlamydial infections. It is sometimes used as a
respiratory infections. Levofloxacin and moxifloxacin are less active second-line anti-tuberculous drug in combination with other agents.
than ciprofloxacin in vitro against enteric gram-negative bacilli and
Pseudomonas aeruginosa, but have been effective in treating urinary tract FOSFOMYCIN (Monurol) —Can be used as a single-dose oral agent
infections and other systemic infections caused by these organisms. with moderate effectiveness for treatment of uncomplicated urinary tract
Levofloxacin and moxifloxacin have been used to treat some oxacillin- infections caused by many strains of enteric gram-negative bacilli, ente-
sensitive and oxacillin-resistant S. aureusinfections, although resistance is rococci and some strains of Staphylococcus saphrophyticus, but gener-
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Antibacterial Drugs: A Brief Summary for Quick Reference Antibacterial Drugs: A Brief Summary for Quick Reference
ally not Pseudomonas. It is much more expensive than trimethoprim/sul- enterococcal infections. Linezolid is also active against oxacillin-resist-
famethoxazole. ant Staphylococcus aureus, S. epidermidis and penicillin-resistant
Streptococcus pneumoniae. Reversible thrombocytopenia has occurred,
FURAZOLIDONE (Furoxone) — An oral nonabsorbable antimicrobial especially with therapy for more than 2 weeks. A serotonin syndrome
agent of the nitrofuran group that inhibits monoamine oxidase (MAO). has been observed in patients taking linezolid together with a selective
The manufacturer recommends it for treatment of bacterial diarrhea. Its serotonin receptor inhibitor. Emergence of resistance has been observed
safety has been questioned (oral administration induces mammary with enterococcal and S. aureusstrains.
tumors in rats) and other more effective drugs are available.
LOMEFLOXACIN (Maxaquin) — See Fluoroquinolones
GATIFLOXACIN (Tequin) — See Fluoroquinolones (has been with-
drawn) MACROLIDES
Azithromycin (Zithromax) — A macrolide antibiotic that has much
GEMIFLOXACIN (Factive) — See Fluoroquinolones less gastrointestinal toxicity than erythromycin and is not associated
with drug interactions with the CYP3A cytochrome P-450 enzyme sys-
GENTAMICIN (Garamycin, and others) — See Aminoglycosides tems. A single dose has been effective for treatment of urethritis and cer-
vicitis caused by Chlamydia and for treatment of trachoma.
IMIPENEM/CILASTATIN (Primaxin) — See Carbapenems Azithromycin is useful in treating Mycoplasma pneumoniae, Chlamydia
pneumoniae and Legionella pneumophila pneumonias, as well as some
ISONIAZID (Nydrazid, and others) — A major antituberculosis drug respiratory infections due to Streptococcus pneumoniae, Haemophilus
that can cause fatal hepatitis. Rifampin-isoniazid-pyrazinamide influenzae or Moraxella catarrhalis. However, an increasing number of
(Rifater) and rifampin-isoniazid (Rifamate) are fixed-dose combina- S. pneumoniae strains have become resistant to the macrolides and
tions for treatment of tuberculosis. azithromycin should not be used alone to treat pneumococcal pneumonia
unless the causative strain is known to be sensitive to the macrolides.
KANAMYCIN (Kantrex, and others) — See Aminoglycosides Azithromycin alone is effective for prevention of Mycobacterium avium
infections, and combined with other drugs, such as ethambutol, rifabutin
LEVOFLOXACIN (Levaquin) — See Fluoroquinolones or ciprofloxacin, it is effective for treatment.
LINCOMYCIN (Lincocin) — Similar to clindamycin in antibacterial Clarithromycin (Biaxin) — A macrolide antibiotic similar to
activity and adverse effects. Rarely indicated for treatment of any infec- azithromycin, but with a shorter half-life. It is somewhat more active than
tion because it is less active than clindamycin. azithromycin against gram-positive organisms and less active against
gram-negative organisms. Clarithromycin is effective for prevention of
LINEZOLID (Zyvox)— An oxazolidinone bacteristatic antibiotic avail- Mycobacterium avium infections and, combined with other drugs, for
able in both an oral and intravenous formulation. It is active against treatment of both M. avium and Helicobacter pylori. It has more adverse
Enterococcus faecium and E. faecalis including vancomycin-resistant drug interactions than azithromycin. Clarithromycin is a strong inhibitor
12 13