San Francisco: Study of Septra (Bactrim) Desensitization

Marcus Conant, M. D., will soon begin a study of ways to reduce the
incidence of drug reaction to co-trimoxazole (also called Septra, or
Bactrim; it also has other brand names) in HIV-positive persons. He is
seeking two groups of volunteers:
* Those with T-helper counts less than 250 who have had a reaction
to the drug; and
* Those with T-helper counts more than 400 who have never had a
reaction to co-trimoxazole (whether or not they have ever used the
drug).
For more information about this study, call Mark Dybul, M. D., at
415/923-1333.
Background
Co-trimoxazole is widely believed to be better than aerosol
pentamidine for pneumocystis prophylaxis (prevention); it may also help
to prevent toxoplasmosis. Co-trimoxazole is also much less expensive
than aerosol pentamidine. But many people who are HIV positive cannot
use this drug because of allergic reactions. In the past, Dr. Conant has
had some success with a special protocol for desensitizing patients who
had already developed sensitivity to co-trimoxazole; some of them have
been able to resume its use. The new study attempts to build on this
experience to see if it is possible to prevent the reaction in the first
place; it is seeking quantitative data which can be used widely to
improve the general standard of care.