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Concern · Acne · Inflammatory

P. 26 · GUIDE

Red papules, pustules,
and the resistance question.

Papules, pustules, nodules. BPO + retinoid + sometimes oral.

The painful, red, often pustular lesions that distinguish inflammatory acne from comedonal. The protocol shifts from retinoid-led to retinoid-plus-bactericidal, with a careful eye on antibiotic resistance — the single under-discussed risk in the category.

— § 01

The triggers worth tracking.

Red, raised, tender papules

The lesion that hurts when you press it. Inflammation is the dominant feature, not congestion.

94%
Pustules with white-yellow heads

The classic 'pimple.' BPO and topical retinoid is the workhorse combination.

82%
Cysts or nodules (deep, painful)

If present, escalate to a dermatologist. OTC routine alone is insufficient and risks scarring.

38%
Post-inflammatory pigmentation after healing

The shadow that remains for months after the lesion clears. Treat in parallel — see PIH guide.

76%
⁂

— § 02

Ingredients that actually work.

Tier
Molecule
Role
Evidence
Tier A
Benzoyl peroxide 2.5%
Bactericidal
First-line. Prevents C. acnes resistance. Pair with adapalene; spot-treat at first.
Tier A
Adapalene 0.1%
Retinoid
OTC. Reduces both inflammatory and comedonal lesions. 12-week ramp.
Tier B
Clindamycin 1% topical
Antibiotic
Effective; never use as monotherapy. Always pair with BPO to prevent resistance.
Tier A
Azelaic 15%
Anti-inflammatory + comedolytic
Pregnancy-safe; useful in adult inflammatory cases. Slower than retinoids.
Tier A
Oral isotretinoin (clinic)
Sebum suppression
Reference treatment for moderate-severe disease. Requires monitoring; remarkable endpoints.
Tier A
Spironolactone (clinic)
Anti-androgen
First-line for adult female hormonal inflammatory acne. Not for male patients.
⁂

— § 03

The protocol.

  1. Phase 01 · Week 1–2

    BPO + barrier

    BPO 2.5% wash 3× per week. Cleanser, ceramide moisturiser, SPF. No actives stacked yet.

  2. Phase 02 · Week 3–6

    Add adapalene

    Adapalene 0.1% PM, alternate nights. BPO 2.5% spot AM as needed. Watch for resistance signs.

  3. Phase 03 · Week 6–12

    Combination

    Adapalene + BPO 2.5% combination (Epiduo) is the simplest single-product version of the gold standard.

  4. Phase 04 · Month 4+

    Reassess

    If inadequate response: dermatologist for oral spironolactone, doxycycline, or isotretinoin. Do not loop on OTC alone.

Bottom line

If you have not improved on adapalene + BPO at month 4, see a clinician. Looping on OTC for a year leaves scars that no protocol can undo.