Safety of dapsone as Pneumocystis carinii pneumonia prophylaxis in human immunodeficiency virus-infected patients with allergy to trimethoprim/sulfamethoxazole.
OBJECTIVE
To assess the safety of dapsone prophylaxis of Pneumocystis carinii pneumonia (PCP) in patients with prior intolerance to trimethoprim/sulfamethoxazole (TMP/SMX).


METHODS
We conducted a retrospective study in the categorical human immunodeficiency virus out-patient program of a university hospital. Patients who had filled prescriptions for dapsone at our pharmacy between January 1991 and April 1994 were evaluated and 75 patients were found eligible for analysis.


RESULTS
The overall incidence of adverse events (AE) in our study cohort was 39%. The most common AEs were anemia (23%) and rash (16%). However, after critical evaluation of each case, only 3 cases of anemia (4%) and 2 cases of rash (3%) were judged to be "likely related" to dapsone. Only 5/75 patients (7%) developed the same intolerance to dapsone as previously experienced on TMP/SMX, and none of these cases was viewed as "likely related" to dapsone. A dapsone regimen of 100 mg qd and a prior episode of PCP were associated with a higher incidence of AEs. Eight cases of PCP occurred in spite of dapsone prophylaxis for an incidence of 7 cases per 1,000 patient-months. Seven of the cases of PCP occurred in patients who were receiving secondary prophylaxis.


CONCLUSIONS
Given the low incidence of AEs judged to be "likely related" to dapsone, this drug is a reasonable choice for PCP prophylaxis in patients with prior AEs to TMP/SMX.
Beumont
M G
MG
Department of Medicine, University of Pennsylvania Medical Center, Philadelphia, USA.
Graziani
A
A
Ubel
P A
PA
MacGregor
R R
RR
D000328:Adult; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000892:Anti-Infective Agents, Urinary / Q000009:adverse effects*; D003622:Dapsone / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004342:Drug Hypersensitivity / Q000150:complications*; D005260:Female; D015658:HIV Infections / Q000150:complications*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011020:Pneumonia, Pneumocystis / Q000209:etiology / Q000517:prevention & control*; D012189:Retrospective Studies; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000009:adverse effects*
D000890:Anti-Infective Agents; D000892:Anti-Infective Agents, Urinary; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D003622:Dapsone