Derm: STEVENS-JOHNSON SYNDROME, exfoliative dermatitis, hypersensitivity reactions (including erythema nodosum leprosum), photosensitivity, systemic lupus erythematosus.
EENT: blurred vision, pharyngitis (topical), tinnitus.
GI: vomiting, abdominal pain, HEPATOTOXICITY, nausea, PANCREATITIS.
Hemat: hemolytic anemia, AGRANULOCYTOSIS, METHEMOGLOBINEMIA, reticulocytosis.
Neuro: headache, insomnia, mood changes, peripheral neuropathy, tonic-clonic movements (topical), vertigo.
Leprosy
- PO (Adults): 50–100 mg/day for 3–10 yrs.
- PO (Children): 1–2 mg/kg/day, up to 100 mg/day.
Dermatitis Herpetiformis
- PO (Adults): Initiate therapy with 50 mg/day, up to 300 mg/day may be required.
Acne Vulgaris
- Topical (Adults and Children ≥12 yrs): 5% gel: Apply small amount twice daily.
- Topical (Adults and Children ≥9 yr): 7.5% gel: Apply small amount once daily.
Pneumocystis jiroveciiPneumonia
- PO (Adults): Prophylaxis: 100 mg/day;Treatment: 100 mg/day (in combination with trimethoprim) for 21 days.
- PO (Children >1 mo): Prophylaxis: 2 mg/kg/day (up to 100 mg/day) once daily, or 4 mg/kg once weekly (up to 200 mg/dose).
Therapeutic Classification: leprostatic agent, anti-infectives
Absorption: Slowly absorbed (70–80%) following oral administration; acidic environment promotes absorption.
Distribution: Widely distributed; crosses the placenta and enters breast milk in significant concentrations.
Protein Binding: Dapsone: 70–90%; MADDS: 99%.
Metabolism/Excretion: Mostly metabolized by the liver to monoacetyl dapsone (MADDS), its major metabolite, which is then metabolized back to dapsone.
Half-life: 10–50 hr.
