Author: Dr Amanda Oakley, Dermatologist, Hamilton, New Zealand,1997.

Dapsone is a sulphone antibiotic medication available for many years to treat leprosy. In New Zealand, 100mg and 25mg tablets are available.

Dapsone is also used for treating various skin conditions including:

Dapsone treatment requires careful laboratory monitoring.

It has some important side effects, which are more likely with higher doses. If you are on dapsone, follow your doctor's instructions carefully, and let him or her know if you start any new medications.


You should not take dapsone if you are allergic to it. Let your doctor know if you are allergic to sulphur antibiotics - dapsone is usually well tolerated, but it should be started cautiously.

If you have significant heart or lung disease, the dose of dapsone may have to be lower because of the drug's effect on oxygen carrying capacity of your blood cells.

Dapsone should be avoided during pregnancy and breast feeding.

Side effects: minor, relatively infrequent

Side effects of greater importance

Rare, but potentially serious side effects

Usually, a blood test is performed as a base-line before starting dapsone. It is then checked after about a week on therapy, and then about once a month, depending on the dose and state of the blood count.

Follow instructions precisely regarding the timing of these tests.

Dapsone gel

Dapsone gel 7.5% once daily (trade name Aczone®) is available in the US and Australia for topical treatment of acne. It is usually well tolerated, but rarely causes the skin at the site of application to become dry and red. There is a low risk of haemolysis and the other side effects of oral treatment described above.

New Zealand approved datasheets are the official source of information for these prescription medicines, including approved uses and risk information. Check the individual New Zealand datasheet on the Medsafe website.

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