What Rosacea Actually Is
Rosacea is a chronic, relapsing inflammatory skin disorder of the central face — forehead, cheeks, nose, and chin — characterised by vascular dysfunction, neurogenic inflammation, and dysbiosis of the skin microbiome (particularly elevated Demodex density and altered bacterial composition).
It affects an estimated 5–10% of the global population and is frequently misdiagnosed as acne, eczema, or simple sensitivity. The distinction matters because most conventional acne treatments — particularly harsh AHAs, strong retinoids, and benzoyl peroxide — can severely worsen rosacea.
The Four Subtypes
| Subtype | Presentation | Primary Features |
|---|---|---|
| ETR (Erythematotelangiectatic) | Persistent central redness, flushing, visible blood vessels | Vascular — telangiectasia, diffuse redness, burning/stinging |
| PPR (Papulopustular) | Acne-like papules and pustules with background redness | Most commonly misdiagnosed as acne; no comedones |
| Phymatous | Skin thickening, irregular texture | Rhinophyma (nose enlargement); more common in males |
| Ocular | Eye irritation, redness, watering | Often accompanies other subtypes; requires ophthalmology input |
Identifying Personal Triggers
Rosacea has no universal trigger set — triggers are highly individual. The most common:
- UV radiation (most consistent universal trigger)
- Heat: hot showers, exercise, hot drinks, saunas
- Emotional stress (neurogenic flushing via neuropeptide release)
- Alcohol — particularly red wine, spirits (histamine, prostaglandin release)
- Spicy foods — capsaicin activates TRPV1 receptors → neurogenic flushing
- Skin products containing fragrance, alcohol denat., eucalyptus, menthol
The trigger diary: Track meals, environment, products, and stress levels alongside flare incidents for 4–6 weeks. Patterns emerge that are specific to your rosacea — not generalisable to everyone's.
Evidence-Based Topical Approach
- Azelaic acid 15–20%: Anti-inflammatory, reduces papulopustular lesions, mildly reduces redness — first-line topical
- Ivermectin 1% (Rx): Targets Demodex overgrowth and has anti-inflammatory properties — strong RCT evidence for PPR subtype
- Niacinamide 5%: Anti-inflammatory, vasoconstrictive, barrier-supportive — well-tolerated in rosacea
- Metronidazole 0.75–1% (Rx): Antimicrobial and anti-inflammatory; standard Rx first-line for PPR
- Brimonidine tartrate 0.5% (Rx): Alpha-adrenergic agonist — vasoconstricts for up to 12 hours; for ETR subtype redness
For the microbiome dysfunction underlying rosacea, see Skin Microbiome. For the gut-rosacea link, see Gut-Skin Axis.