a. Erythromycin is a product of the fungus Streptomycesery threus, which was
first found in a soil sample collected in the Philippine Islands. This agent inhibits protein
synthesis to exert bacteriostatic activity.
b. Erythromycin is acid labile unless it is formulated in an enteric coated form or
is combined with a salt such as stearate or ethylsuccinate. It is distributed to most body
tissue and is prominent in prostatic fluid. There is minimal concentration of this agent in
the CSF unless there is meningitis.
c. The clinical spectrum of this agent is similar to penicillin G, and it is the drug
of choice in the treatment of mycoplasma pneumonia and Legionnaire's disease. It is a
useful substitute for penicillin in people who are hypersensitive to penicillin.
d. Adverse reactions to erythromycin are similar to the penicillins except that
estolate salt has been known to cause cholestatic hepatitis. Therefore, it should not be
used in patients with pre-existing liver disease. Large oral doses of erythromycin can
cause epigastric distress.
e. As an antibiotic agent, erythromycin can be found in the following
preparations: Erythromycin base (EMycin), Erythromycin estolate (Ilosone),
Erythromycin stearate (Erythrocin), and Erythromycin ethylsuccinate (E.E.S. ).
3-11. CLINDAMYCIN (CLEOCIN)
a. Clindamycin is derived from the actinomycete Streptomyces lincolnensis. A
bacteriostatic agent suppresses protein synthesis.
b. When taken orally, absorption of clindamycin is rapid and almost complete. It
is widely distributed to body tissues with the exception of the CSF (cerebrospinal fluid).
c. Enzymes in the liver accomplish metabolism of the agent. The metabolites
are excreted through the urine and bile.
d. Clindamycin is indicated in the treatment of serious infections caused by
anaerobic bacteria. It is the drug of choice for use against Bacteroides fragilis.
e. Adverse reactions noted with the use of clindamycin include abdominal pain,
esophagitis, nausea, vomiting, and diarrhea. Colitis, which can be fatal, is a serious
reaction to this agent. Consequently, other less toxic agents, such as erythromycin or
penicillin, should be used if possible. If significant diarrhea or colitis appears while the
patient is using clindamycin, its use should be discontinued. This colitis can then be
treated with the agent vancomycin.