How Duac Treats Acne

1% Clindamycin Phosphate and 5% Benzoyl Peroxide

Duac is a prescription medication used to treat mild to moderate inflammatory acne. It’s a combination of two acne-fighting medications: clindamycin (1%) and benzoyl peroxide (5%). It can be used by both teens and adults. 

A young man applying acne cream to his face
AzmanL / Getty Images

How Duac Works

Benzoyl peroxide is a super common acne treatment ingredient. You’ve probably seen it in a myriad of over-the-counter acne products, plus many prescription medications as well. Why is it so popular? Because benzoyl peroxide helps keep the pore clear of blockages while making it a less hospitable home for acne-causing bacteria.

Clindamycin, an antibiotic that in this case is used topically, works a bit differently. It reduces the amount of acne-causing bacteria found on the skin. The cool thing is that working together, they tend to get a better result than benzoyl peroxide or topical clindamycin alone.

Similar Medications

Duac isn’t the only medication with the benzoyl peroxide/clindamycin combination. Acanya, BenzaClin, Onexton, are other combo treatments with the same active ingredients although the percentage of medication is different in each. (For example, Acanya contains 2.5% benzoyl peroxide compared to Duac’s 5%.)

How to Use It

Generally, Duac is applied just once per day, usually in the evening. (Your dermatologist may have a different plan for you, though, so make sure to follow his or her instructions.)

The package insert recommends using a "fingertip" sized amount of gel for the entire face. You'll need to apply it over the entire face and not just on individual pimples. Duac will help keep new pimples from forming, but only if it's applied over the entire area.

Be Patient

Duac won't work overnight, or even over several nights. Expect to use it consistently for several weeks before really noticing an improvement in your skin.


If you have ulcerative colitis or Crohn’s disease, Duac isn’t the right acne treatment choice for you. Ditto or if you have ever had severe diarrhea when using antibiotics. You can’t use Duac along with any erythromycin medication, either. There are currently no good studies demonstrating the use and safety of Duac during pregnancy, therefore, it’s unclear how it may affect a developing fetus. It's important to let your healthcare provider know if you are pregnant or are nursing. There are other acne treatment choices that are a better fit for pregnant moms.

Side Effects

Like all medications, Duac can cause side effects. The good news is, side effects are usually mild. They’re similar to what you’d get with other acne medications. Most likely are:

  • Dry skin
  • Peeling or flaking
  • Redness or irritation
  • Burning

These usually aren't too bothersome, but let your practitioner know if they become severe. More serious (but much less common) side effects include diarrhea, bloody stools, and stomach cramps. You’ll want to tell your healthcare provider right away if you develop any of these.

Don't Forget the SPF

Duac can cause photosensitivity. The added benefit of regularly using sunscreen is that you’ll protect your skin from premature aging. No better time to start than now.

The Benzoyl Peroxide in Duac Can Bleach Your Linens

Wash your hands with soap right after applying your medication. Don’t let the gel get on your clothing, pillowcases, towels, etc. or you’ll end up with lovely orange stains.

If you're applying just before bed, you'll probably want to use a white pillowcase. Other colors have a tendency to bleach out, even if the medication is fully dry before going to bed. And wear pajamas that you won’t be devastated by if they become stained.

Ask Your Dermatologist

Your dermatologist is a wealth of information, so take advantage of this resource. Ask questions, make sure you know exactly how to use your Duac, and if you have any concerns, let your dermatologist know.

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3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. Food and Drug Administration. Duac: clindamycin phosphate and benzoyl peroxide gel. Highlights of prescribing information. Updated December 2013.

  2. Guerra-Tapia A. Effects of benzoyl peroxide 5% clindamycin combination gel versus adapalene 0.1% on quality of life in patients with mild to moderate acne vulgaris: a randomized single-blind study. J Drugs Dermatol. 2012;11(6):714–22.

  3. Grove G, Zerweck C, Gwazdauskas J. Tolerability and irritation potential of four topical acne regimens in healthy subjects. J Drugs Dermatol. 2013;12(6):644–9.