Dapsone gel: what it treats, how to use it, side effects
Last updated September 3, 2026.
Dapsone gel (brand name Aczone, 7.5%) is a once-daily prescription gel for acne, applied to the whole face. It is the acne-drug version of an old anti-infective, and it performs especially well in adult women with inflammatory breakouts.
What does it treat?
Acne vulgaris in patients 9 and older: inflamed pimples and pustules primarily. It is anti-inflammatory and antibacterial. In trials, women, particularly adult women, saw the strongest responses, which is why dermatologists reach for it in that group; it is also a good fit for people who cannot tolerate retinoids or benzoyl peroxide irritation.
How do you take it?
A pea-sized amount in a thin layer to the entire face once daily (the 7.5% gel; the older 5% gel is twice daily), after gentle washing, on dry skin. It treats the face as a field, not spot-by-spot. If there is no improvement after 12 weeks, the label says reassess. One famous quirk: applying it at the same time as benzoyl peroxide can turn skin or facial hair temporarily yellow-orange; it washes off and is harmless, but it startles people. Missed dose: apply when remembered unless the next dose is near.
Side effects to know
- Common: application-site dryness and itching, plus oiliness or peeling; overall very well tolerated.
- Serious: rare methemoglobinemia (blood that cannot carry oxygen properly, with blue-grey lips and fatigue), which is why G6PD deficiency matters, and hemolysis in G6PD-deficient patients. Oral dapsone has a wider risk profile; topical shares only fragments of it.
Who should not take it?
Avoid with congenital or idiopathic methemoglobinemia. G6PD deficiency requires a doctor's weighing, since topical dapsone caused lab signs of red-cell breakdown in some G6PD-deficient patients; many clinicians check the enzyme or simply pick a different acne drug. St. John's wort and acetaminophen interact. Under 9 years old, it is not established. Pregnancy and breastfeeding are doctor conversations.
When is it an emergency?
Call 911 for blue or grey lips, nail beds, or skin, sudden severe fatigue, or shortness of breath after starting, the signature of methemoglobinemia. Pymander's escalation routing is built and tested specifically for this class of decision; see the safety architecture working paper.
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Common questions
Why did my acne gel turn my skin orange?
That is the known interaction between dapsone gel and benzoyl peroxide used at the same time: a temporary yellow-orange discoloration of skin or facial hair. It is harmless and washes off, but the fix is separating the products by time of day or dropping one. It is in both the label and MedlinePlus, so it is expected, not a defect.
Is dapsone gel better for women?
Trials found the largest effects in women, particularly adult women with inflammatory acne, and dermatologists disproportionately prescribe it there. It works in men too, just less dramatically on average. Nobody fully knows why; hormonal-pattern acne along the jaw and chin seems especially responsive.
What is G6PD deficiency and why does it matter here?
G6PD deficiency is a common inherited red-cell enzyme variant, most frequent in people of African, Mediterranean, and Southeast Asian descent, that leaves red cells vulnerable to certain drugs. Topical dapsone caused lab signs of red-cell breakdown in some G6PD-deficient users, so known deficiency means a conversation about testing or alternatives.
How long until my acne improves?
Give it the full 12 weeks; that is the label's own reassessment point. Many see earlier progress, but acne treatments all work on the multi-week scale of skin turnover. No meaningful improvement at 12 weeks means switching or combining, not doubling the dose.
Can I use it with my other acne products?
Mostly yes: it layers fine with retinoids, salicylic acid, and oral treatments under a dermatologist's plan. The one to separate is benzoyl peroxide (the staining issue). MedlinePlus also flags St. John's wort and acetaminophen as interactions to disclose.
Is it antibiotic resistance a concern like with clindamycin?
Dapsone is a sulfone, not a typical antibiotic, and resistance-driven failure is far less prominent than with topical clindamycin or erythromycin. That is one reason it is chosen for longer-term maintenance when a retinoid alone is not enough.