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Other names:

Diaminodiphenylsulfone; Diaphenylsulfone

Often used for:


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What is dapsone?

Dapsone is a medication used to prevent or treat Pneumocystis pneumonia (also known as PCP or PJP pneumonia). PCP/PJP pneumonia is a lung infection caused by the fungus Pneumocystis jirovecii. Patients with weak immune systems are at highest risk. Dapsone is usually given to patients who cannot take Sulfamethoxazole/Trimethoprim (SMX/TMP, Bactrim®, Septra®).

Dapsone is also used to treat certain skin problems.

Before starting dapsone, patients may be tested for low levels of an enzyme called G6PD. A G6PD deficiency can cause break down of red blood cells with some medicines.

Patients receiving dapsone may have regular blood draws to check blood counts and monitor liver function.

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May be given as a tablet by mouth

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May be given as a liquid by mouth

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Possible side effects

  • Nausea and vomiting
  • Skin irritation, sun sensitivity
  • Liver problems
  • Loss of appetite
  • Headache
  • Fever
  • Abdominal pain
  • Sleep problems
  • Dizziness
  • Blurry vision
  • Muscle weakness, burning or tingling in hands or feet
  • Loss of fertility in males

Not all patients who take dapsone will experience these side effects. Common side effects are in bold, but there may be others. Please report all suspected side effects to your doctor or pharmacist.

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Tips for families

Be sure to discuss these and other recommendations with your doctor or pharmacist.

  • Take all doses as prescribed.
  • Patients should protect their skin from the sun while taking this medicine.
  • Patients should tell their doctor if they are pregnant or breastfeeding.

Dapsone at home:

  • Dapsone can be taken with or without food. Take with food if stomach upset occurs.
  • Store at room temperature. Protect from light.
  • Give a missed dose as soon as possible. If it is near the time of the next dose, skip the dose. Do not give 2 doses at the same time.
  • Do not use the medicine past the expiration date.
  • Follow instructions for safe storage and disposal.

Dapsone resources