Cotrimoxazole
Adverse Effect: an increased risk of dapsone toxicity (hemolytic anemia, methemoglobinemia, peripheral neuropathy) or trimethoprim toxicity (bone marrow depression, thrombocytopenia, leukopenia, megaloblastic anemia) Clinical Management: Monitor dapsone toxicity or Cotrimoxazole toxicity adjust dosages or discontinue one of the drugs if necessary. This interaction may be more pronounced in AIDS patients with acute illness.
Probenecid
Adverse Effect: an increased risk of dapsone toxicity (hemolytic anemia, methemoglobinemia, lethargy, weakness) Clinical Management: Patients who require the concurrent use of these drugs should be monitored more closely for development of dapsone-related toxicity (hemolytic anemia, methemoglobinemia, lethargy, weakness).
Rifampicin
Adverse Effect: decreased dapsone effectiveness Clinical Management: Monitor decreased dapsone efficacy; adjust the dose if needed.
Zidovudine
Adverse Effect: hematologic toxicity (neutropenia) Clinical Management: If concomitant use of dapsone and zidovudine is necessary, temporary withdrawal or dose reductions of dapsone and/or zidovudine are recommended. Blood counts should be monitored frequently.
Barbiturates, ritampin: May be as-sociated with increased hepatic metabolism of dapsone. Monitor child for lack of efficacy.
Didanosine: May produce possible therapeutic failure of dapsone, leading to increase in infec-tion. Avoid use together.
PABA: May antagonize effect of dapsone by in-terfering with primary mechanism of action. Mon-itor child for lack of efficacy.
Probenecid: Reduced urinary excretion of dap-sone metabolites, increasing plasma levels. Mon-itor child closely.
Trimethoprim: Increased serum levels of dapsone and trimethoprim may occur when used togeth-er, possibly increasing pharmacologic and toxic effects of each. Monitor child closely. |