Rosacea

What it is

Rosacea is a chronic inflammatory skin condition affecting an estimated 5–10% of the global population, characterized by persistent central facial redness, visible blood vessels (telangiectasia), and in many cases inflammatory papules and pustules that resemble acne. Also called acne rosacea in older literature — though that term is now discouraged because it implies a shared mechanism with acne that does not exist — rosacea primarily affects the cheeks, nose, chin, and forehead, and can extend to the eyes (ocular rosacea). It is more common in women, though men who develop it tend to have more severe presentations, including rhinophyma (a progressive thickening and enlargement of the nose). Onset typically falls between ages 30 and 60, with the highest prevalence in people with fair skin and northern European ancestry — a demographic well represented in Canada's population.

Hormonal changes are a recognized driver of rosacea onset and flare frequency. Perimenopause and menopause are among the strongest hormonal triggers: declining estrogen destabilizes facial vasomotor control, producing hot flashes and flushing that overlap with and amplify rosacea's own vascular reactivity. Many Canadian women first notice rosacea — or a sharp worsening of existing rosacea — during the perimenopausal transition. Understanding this hormonal dimension is important for comprehensive management, particularly when a patient is also a candidate for menopausal hormone therapy (MHT).

Causes and mechanism

Rosacea is multifactorial. No single cause explains all presentations, but four overlapping mechanisms are well established:

1. Neurovascular dysregulation — facial blood vessels react abnormally to stimuli, producing excessive flushing and persistent redness.
2. Innate immune activation — overexpression of antimicrobial peptides called cathelicidins drives chronic skin inflammation.
3. Demodex mite overpopulation — higher-than-normal densities of Demodex folliculorum mites on facial skin trigger immune responses in rosacea-prone individuals.
4. Skin barrier dysfunction — an impaired epidermal barrier increases sensitivity and inflammatory reactivity to environmental triggers.

Hormonal contributors sit on top of these mechanisms. Declining estrogen at menopause intensifies vasomotor instability, so menopausal flushing and rosacea flushing reinforce each other. Some women also report cyclical flares around menstruation, possibly linked to prostaglandin-mediated inflammation. Emerging research suggests associations between rosacea and thyroid autoimmunity, with elevated thyroid autoantibodies and prolactin levels found in some rosacea cohorts — though causality has not been established.

Common external triggers include UV radiation (the most consistently reported trigger), heat, alcohol, hot beverages, spicy food, emotional stress, and certain topical products. Rosacea also has a strong genetic component and runs in families.

Symptoms and diagnosis

Rosacea is classified into four subtypes, though overlap between them is common:

Subtype	Key features	Notes
1 — Erythematotelangiectatic	Persistent central redness, visible vessels, frequent flushing, skin sensitivity	Most common in women
2 — Papulopustular	Central redness plus inflammatory papules and pustules	Often mistaken for adult acne
3 — Phymatous	Skin thickening, irregular texture; rhinophyma most common	More common and severe in men
4 — Ocular	Eye redness, gritty sensation, eyelid inflammation (blepharitis), light sensitivity	Can precede skin findings

Diagnosis is clinical — based on the characteristic central-face distribution and pattern of changes. There is no specific blood test for rosacea. When menopausal or thyroid-related flushing is suspected as a contributing factor, clinicians may order FSH, estradiol, and TSH to clarify the picture. Skin biopsy is rarely needed but can help in diagnostically uncertain cases. In Canada, initial assessment is typically done by a family physician or nurse practitioner, with referral to dermatology for moderate-to-severe or treatment-resistant presentations. LifeLabs and Dynacare both process the hormonal panels that may accompany a rosacea workup.

Treatment options

Rosacea cannot be cured, but it can be effectively controlled. Treatment is matched to subtype and severity.

Sun protection and trigger avoidance form the foundation of management. Daily broad-spectrum SPF 30 or higher sunscreen is the single most important preventive measure. A trigger diary helps identify individual patterns before making sweeping dietary or lifestyle changes.

Topical treatments include:

• Azelaic acid — reduces inflammation, redness, and papules; suitable for long-term use
• Metronidazole gel or cream — reduces inflammation and papules
• Ivermectin 1% cream (Soolantra) — targets Demodex mites; particularly effective for papulopustular rosacea
• Brimonidine gel or oxymetazoline cream — vasoconstrictors for acute redness; effects are temporary and do not modify the underlying condition

Oral treatments include low-dose doxycycline (40 mg modified-release), which works as an anti-inflammatory rather than an antibiotic at this dose and is the standard oral option for papulopustular rosacea. Low-dose isotretinoin is reserved for severe or refractory cases.

Procedural treatments — laser therapy and intense pulsed light (IPL) — target visible blood vessels and persistent redness and are effective for erythematotelangiectatic rosacea. Rhinophyma is managed surgically.

Hormonal management: For perimenopausal and postmenopausal women in whom vasomotor flushing is a significant rosacea trigger, MHT can indirectly reduce flare frequency by stabilizing the vasomotor instability that drives flushing. This is not a rosacea treatment per se, but the overlap between menopausal flushing and rosacea flushing means that treating one can benefit the other. The Society of Obstetricians and Gynaecologists of Canada (SOGC) supports MHT as appropriate for eligible women with bothersome vasomotor symptoms.

When to see a clinician in Canada

See a family physician, nurse practitioner, or dermatologist if:

• Persistent central facial redness, visible blood vessels, or acne-like bumps have lasted more than a few weeks
• Flushing episodes are frequent and affecting daily life or confidence
• Eye symptoms are present — redness, irritation, or a gritty sensation — because untreated ocular rosacea can cause corneal damage
• Over-the-counter products have not improved symptoms after 8–12 weeks
• You are in perimenopause or postmenopause and have noticed worsening facial flushing or new skin changes

For Canadians seeking care that addresses both the dermatological and hormonal dimensions of rosacea, telehealth platforms such as Felix, Maple, Cleo, Phoenix, and others can facilitate initial assessment and prescriptions, with referral to dermatology when needed. Early treatment consistently produces better long-term outcomes than waiting for symptoms to progress.

Limitations and open questions

Research is still emerging on several aspects of rosacea. The precise relationship between rosacea and thyroid autoimmunity is not yet established — associations have been reported, but it is unclear whether thyroid dysfunction causes rosacea, shares common immune pathways, or is coincidental. The role of the gut microbiome in rosacea pathogenesis is an active area of investigation with no definitive clinical guidance yet. Evidence on whether MHT directly improves rosacea outcomes — as opposed to indirectly reducing flushing triggers — is limited to observational data; no randomized controlled trials have specifically examined this question. Health Canada has not issued specific guidance on rosacea management, and provincial drug benefit coverage for prescription topicals such as ivermectin cream varies by province and formulary. Patients should verify coverage through their provincial plan or private insurer.