Intravenous amphotericin b causes infusion related

Intravenous amphotericin B causes infusion related
hypotension (via histamine release), fever, and chills,
which may be attenuated by the prior administration
of NSAIDs and antihistamines. Adrenal steroids may
provide supplementary stress support. Amphotericin
B binds to ergosterol in fungal membranes, opening
pores and disrupting membrane permeability.
For antitubercular activity, isoniazid (INH) must
first be metabolically activated via a catalase
present in mycobacteria. A decrease in
expression of the cat G gene that encodes this
enzyme is the mechanism of high-level
resistance to INH.
Azithromycin is highly effective as an oral agent in
the management of pharyngitis caused by gram-
positive cocci and may necessitate only a short
course of therapy. In patients who have marked
hypersensitivity to penicillins, it is inappropriate to
use a cephalosporin, even though cefaclor is active
against common oropharyngeal pathogens.
Doxycycline should not be used in children. One
must assume that complete cross-allergenicity exists
between different members of the penicillin class of
antibiotics, and, in any case, penicillin G is not usually
given orally because of its lability in gastric acid.
Vancomycin would need parenteral administration,
and this antibiotic should be reserved for more
serious bacterial infections.
Organisms associated with sexually
transmitted diseases include chlamydia,
Neisseria gonorrhea, Treponema (syphilis),
Trichomonas, and Gardnerella vaginalis. The
latter two organisms are effectively treated
with the drug metronidazole. Metronidazole
has a chemical structure that results in a
disulfiram-like effect on aldehyde
dehydrogenase, causing reactions with
ethanol. Patients should be cautioned not to
consume alcoholic beverages while on this
drug.

Chapter 5
●
Antimicrobial Drug List and Practice Questions
203
5. An 82-year-old hospitalized patient with creatinine clearance of 25 mL/
min has a microbial infection requiring treatment with antibiotics. Which
of the following drugs is least likely to require a dosage adjustment, either
a smaller dose than usual or an increased interval between doses?
A. Amphotericin B
B. Ceftriaxone
C. Gentamicin
D. Imipenem- cilastatin
E. Vancomycin
6. What drug is most likely to be effective in most diseases caused by
nematodes?
A. Chloroquine
B. Mebendazole
C. Metronidazole
D. Praziquantel
E. Pyrimethamine
7. What antibiotic effectively treats a variety of causative organisms for
bacterial pneumonia, and also works at the 50S ribosomal subunit?
A. Azithromycin
B. Ceftriaxone
C. Doxycycline
D. Ofloxacin
E. Clindamycin
8. In bacterial meningitis, third-generation cephalosporins are common
drugs of choice. However, in neonatal meningitis they would not provide
coverage if the infection was due to which of the following organisms?