Evidence‑Based Triggers and Exacerbating Factors for Rosacea

Environmental Triggers

Ultraviolet radiation, temperature extremes, specific dietary exposures, mechanical irritation, and certain medications are identified as the most important triggers of rosacea flare‑ups in genetically susceptible individuals【1】【2】.
Exposure to hot environments and low humidity aggravates erythema, especially in patients with the erythematotelangiectatic subtype【3】【4】.
Prolonged visual tasks that reduce blink rate (e.g., screen time, reading, driving) worsen ocular rosacea symptoms【4】.

Air‑conditioning, heating, wind, and drafts exacerbate ocular discomfort and facial erythema in rosacea patients【4】【5】.

Systemic isotretinoin markedly increases rosacea symptoms by disrupting tear function and meibomian gland activity【3】【5】.
Dupilumab is associated with conjunctivitis, keratitis, and blepharitis in 32‑55 % of treated patients, leading to worsening of ocular rosacea【3】.
Diuretics, antihistamines, anticholinergics, antidepressants, and systemic retinoids exacerbate dry‑eye symptoms and facial erythema【4】【5】.

Instilling preserved eye drops more than four times daily impairs normal tear‑film maintenance【4】【5】.
Preservatives in topical ocular medications can cause corneal epithelial breakdown and aggravate ocular rosacea signs【4】.

Higher density of Demodex folliculorum on the skin correlates with increased inflammatory markers in rosacea‑affected areas【6】【7】.
An elevated Demodex load is observed in individuals with rosacea, supporting a pathogenic role for the mite【3】.
Cylindrical dandruff at the base of eyelashes is a clinical indicator of ocular Demodex infestation【3】.

Seborrheic dermatitis co‑occurs in approximately 74 % of patients with primary meibomitis, a condition frequently linked to ocular rosacea【3】.
Atopic dermatitis shows a strong association with blepharitis and rosacea flare‑ups【3】.

Rosacea can be missed in patients with darker skin tones because telangiectasia and flushing are less conspicuous【3】【4】【5】.
In pediatric patients, ocular manifestations often appear before cutaneous signs, leading to misdiagnosis as chronic keratoconjunctivitis【3】【4】【5】.

Dysregulation of innate and adaptive immunity—including up‑regulation of the antimicrobial peptide cathelicidin, neuropeptides, and pro‑inflammatory cytokines—underlies the pathophysiology of rosacea【8】.