dapsone at a glance
Medicine class
Antibacterial sulfone with anti-inflammatory activity
Main roles
Leprosy combination therapy, dermatitis herpetiformis and other dermatoses, and prevention of malaria or Pneumocystis pneumonia in specified settings
Key safety issue
Can damage red blood cells or reduce their oxygen-carrying ability; risk is greater with G6PD deficiency
Administration
Swallow the tablet with water; the scored tablet may be divided into equal portions when instructed
What is dapsone used for?
The selected UK product is licensed for:
All forms of leprosy, as part of a multidrug regimen
Dermatitis herpetiformis and other dermatoses
Malaria prevention in combination with pyrimethamine
Prevention of Pneumocystis pneumonia in immunodeficient people, particularly those with AIDS
How does dapsone work?
Dapsone limits folate production in susceptible organisms, slowing their growth. It also reduces neutrophil-driven inflammation and reactive oxygen activity, including effects on myeloperoxidase.
dapsone preparations and strengths
Tablet
Route: Oral
Strengths: 50 mg, 100 mg
How to take dapsone
Take dapsone exactly as prescribed and swallow the tablet with water. The selected tablet is scored and can be divided into equal portions. Do not stop treatment without discussing it with the prescriber, particularly when it forms part of combination therapy.
Check the dispensing label and package leaflet.
Keep scheduled blood-test appointments.
Tell the prescriber or pharmacist about new prescribed, non-prescription or herbal products.
dapsone side effects
Common or expected effects
- Breakdown of red blood cells, which may cause tiredness or pallor
- Methaemoglobinaemia, which may cause breathlessness, headache, dizziness or blue-grey skin
Get urgent medical advice
- Dapsone hypersensitivity syndrome, typically involving rash and fever and potentially affecting the liver, kidneys, blood or nervous system
- Severe blistering, peeling or widespread skin reactions
- Agranulocytosis, suggested by fever, sore throat, mouth ulcers or other signs of infection
- Haemolytic anaemia, jaundice or clinically significant methaemoglobinaemia
- Hepatitis or jaundice
- New tingling, weakness or other peripheral neuropathy symptoms
dapsone in pregnancy
Pregnancy requires an individual specialist or prescriber assessment because evidence is limited and the need for treatment matters. UK rheumatology guidance considers that dapsone may be used during pregnancy; product information notes that benefits for treating leprosy may outweigh potential risk. Folic-acid supplementation may be considered by the treating clinician.
dapsone while breastfeeding
Dapsone passes into breast milk, and haemolytic anaemia has been reported in a breastfed infant. Breastfeeding may sometimes continue after specialist risk assessment, but the infant may need monitoring for haemolysis or jaundice, particularly if newborn, premature or G6PD-deficient.
dapsone interactions
Important documented interactions include:
Probenecid
Reduces dapsone excretion and may increase its blood concentration and adverse effects.
Rifampicin
Increases dapsone clearance and may reduce dapsone exposure.
Trimethoprim
Concurrent use has increased concentrations of both medicines in people with AIDS, potentially increasing toxicity.
Common questions about dapsone
Answers are fully visible for fast scanning and source review.
Why are blood tests needed?
Dapsone can affect red and white blood cells and liver function. Testing helps identify toxicity before it becomes severe.
Why does G6PD deficiency matter?
G6PD deficiency makes red blood cells more vulnerable to oxidative damage and haemolysis; severe deficiency is a contraindication for the selected product.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.