Bactrim
(Co-trimoxazole)
Sulfamethoxazole
and trimethoprim
The importance of the
sulphonamides has decreased as a
result of increasing bacterial
resistance and their replacement by
antibacterials which are generally
more active and less toxic.
Sulfamethoxazole
(sulphamethoxazole) and trimethoprim
are used in combination because of
their synergistic activity. However,
co-trimoxazole is associated with
rare but serious side-effects (e.g.
Stevens-Johnson syndrome and blood
dyscrasias, notably bone-marrow
depression and agranulocytosis)
especially in the elderly (see CSM
recommendations below).
| CSM
recommendations.
Co-trimoxazole should be
limited to the role of drug
of choice in Pneumocystis
carinii pneumonia; it is
also indicated for toxoplasmosis
and nocardosis. It
should now only be considered
for use in acute
exacerbations of chronic
bronchitis and infections
of the urinary tract when
there is good bacteriological
evidence of sensitivity to
co-trimoxazole and good
reason to prefer this
combination to a single
antibacterial; similarly it
should only be used in acute
otitis media in children
when there is good reason to
prefer it. |
Trimethoprim
can be used alone for urinary- and
respiratory-tract infections and for
prostatitis, shigellosis, and
invasive salmonella infections.
Trimethoprim has side-effects similar
to co-trimoxazole, but they are less
severe and occur less frequently.
British National
Formulary, published by the British
Medical association and the Royal
Pharmaceutical Society of Great
Britain. March 2003.