This answer covers PanOxyl's benzoyl peroxide washes and cosmetic retinol; if you mean a prescription retinoid such as tretinoin, follow your prescriber's specific routine instead.4

Why use both?

Benzoyl peroxide reduces acne causing bacteria, while retinol helps prevent clogged pores and can fade dark spots. Retinol belongs to the retinoid family. Combining benzoyl peroxide with a retinoid is an established acne treatment approach, including for darker skin tones, but your particular retinol product still needs its own directions. Retinol comes in several formats, so a serum is not a separate skincare species just because it has a dropper.345

Should I choose 4% or 10% PanOxyl?

PanOxyl Acne Creamy Wash contains 4% benzoyl peroxide; Acne Foaming Wash contains 10%. PanOxyl positions the creamy wash for mild to moderate acne and the foaming wash for more severe acne. Choose between the washes for your needs, not because "maximum strength" sounds like a job title. General benzoyl peroxide guidance is to start with the lowest strength. Between these two washes, that is 4%, although lower strengths exist outside this pair. For darker skin tones, dermatologists suggest starting at 2.5% to limit irritation.1256

How should I use PanOxyl and retinol?

Once the combination has been cleared for you, one practical arrangement is PanOxyl in the morning and retinol at bedtime. This is general routine guidance, not a requirement printed on the PanOxyl label.36

  1. 1In the morning, wet the area. For PanOxyl Acne Foaming Wash 10%, massage the wash into skin for 1 to 2 minutes, rinse thoroughly and pat dry. PanOxyl directs starting once daily, increasing only if needed or directed.
  2. 2Use moisturizer and sunscreen during the day. Choose sunscreen with broad spectrum protection, SPF 30 or higher, and water resistance. Seek shade and use protective clothing too.
  3. 3Before introducing retinol, test a little on a small area. Wait a couple of days and check for redness or itching before adding it to your routine.
  4. 4At bedtime, cleanse gently and pat dry. Follow your retinol package directions; general guidance is a thin, pea sized amount for the face, avoiding the mouth, nose and eyes.
  5. 5Start retinol every other evening for the first couple of weeks, or less often if needed. Finish with a moisturizer labeled noncomedogenic, meaning it will not clog pores. For prescription retinoids, ask your dermatologist before changing frequency or application order.
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How long before I see a difference?

Benzoyl peroxide usually starts working within about four weeks. Acne treatment commonly takes at least six to eight weeks before fewer breakouts appear, and some topical retinoids take 12 weeks or longer. Retinol can leave acne looking worse initially. Worsening acne still deserves advice rather than automatically being dismissed as a purge: speak to a pharmacist or doctor if acne worsens or has not improved after 12 weeks.2347

When should I pause or get help?

Dryness, peeling, itching and burning can occur with either ingredient. Use benzoyl peroxide less often if irritation develops, and get advice if symptoms bother you or persist. Sensitive skin needs particular care; retinoids can worsen eczema. Avoid benzoyl peroxide on broken or infected skin and keep it away from eyes and mouth. Stop using it and seek emergency help for throat or tongue swelling or difficulty breathing.27

If you are pregnant or planning pregnancy, get medical advice before using retinol or another retinoid because of pregnancy risks. Benzoyl peroxide can usually be used during pregnancy, but check first. During breastfeeding, ask about both products and do not apply benzoyl peroxide to the breasts.237

Where this answer comes from

  1. 1About Benzoyl Peroxidepanoxyl.com
  2. 2Benzoyl peroxide: a medicine to treat acnenhs.uk
  3. 3Retinol: Cream, Serum, What It Is, Benefits, How To Usemy.clevelandclinic.org
  4. 4Acne: Diagnosis and treatmentaad.org
  5. 510 tips for clearing acne in darker skin tonesaad.org
  6. 6Acne Foaming Wash Benzoyl Peroxide 10%panoxyl.com
  7. 7Topical retinoids (vitamin a creams)dermnetnz.org