Synopsis
Classify acne by lesion type, inflammatory burden, distribution and personal impact; identify scarring risk early; and match treatment intensity and referral to the whole presentation.
- Look for open and closed comedones, inflammatory papules, pustules, nodules, active scars and persistent pigment change across the face, chest and back.
- Severity is multidimensional: count and depth of lesions matter, but distribution, scarring trajectory, persistent pigment change and psychological impact can justify earlier escalation.
- Mild-to-moderate disease usually has comedones with limited papules or pustules and no nodules; moderate-to-severe disease has many inflammatory lesions or nodules and often truncal involvement.
Key red flags
Acne fulminans, systemic illness, rapidly destructive nodules, severe psychological distress, self-harm thoughts, diagnostic uncertainty or an androgenising syndrome require urgent or specialist assessment rather than routine topical escalation.
Sudden ulcerating or crusted painful nodules with fever, malaise or joint pain require same-day specialist discussion because treatment can differ from ordinary severe acne.
Investigation priorities
Establish severity, scar trajectory and a reproducible baseline before treatment.
Management branches
Comedones and a limited inflammatory burden occur without nodules, rapid scarring or major psychological risk.
- Agree one NICE first-line twelve-week option, commonly fixed adapalene with benzoyl peroxide, after checking pregnancy potential, contraindications and preferences.
- Apply to the whole acne-prone area, introduce alternate-day or short-contact use if irritation is likely, and support with gentle non-comedogenic cleanser, moisturiser and sunscreen.