Dapsone

Differential blood count, reticulocytes, liver function tests, kidney function tests, glucose-6-phosphate dehydrogenase activity, methaemoglobin, pregnancy test recommended.

for oral use; in the USA, for topical use (Aczone®)

3 days 1×25 mg/day, 3 days 2×25 mg/day, 3 days 3×25 mg/day, 3 days 2×50 mg/day, possibly up to 150 mg/day, in combination with vitamin E, approx. 600–900 E/day * reduced methaemoglobin formation.

Weeks to days, depending on the condition.

Weeks 1–4: Weekly differential blood count, liver and kidney function tests, methaemoglobin (Met-Hb), reticulocytes if necessary.

Weeks 5–12: Every 2 weeks differential blood count, liver and kidney function tests if necessary, methaemoglobin (Met-Hb), reticulocytes if necessary.
Months 4 to 12: Every 1–3 months: differential blood count, liver and kidney function tests, methaemoglobin, reticulocytes if necessary. From the second year onwards: Every 3–6 months: differential blood count, liver and kidney function tests, methaemoglobin.

Absolute contraindications: sulfonamide allergy, heart failure, pulmonary insufficiency, anaemia, Hb < 90 g/l, pregnancy and breastfeeding.

Relative contraindications: Hb < 110 g/l.

Exposure to harmful substances, vomiting ➝ dose reduction; exertional dyspnoea ➝ dose reduction; anaemia, methaemoglobinaemia >15 %➝ dose reduction, possibly discontinuation; agranulocytosis ➝ dose reduction, possibly discontinuation; eosinophilia, toxic hepatitis, dapsone hypersensitivity syndrome ➝ dose reduction, possibly discontinuation; headache ➝ analgesics