[Rosacea. Systemic therapy with retinoids].

Systemic isotretinoin has been known for decades as an effective and safe therapeutic option in the treatment of severe and refractory forms of rosacea. It can also be used in special treatment-resistant forms of rosacea, e.g. granulomatous rosacea, as efficacious second-line therapy. Previously, the effect of isotretinoin in rosacea has been mainly studied in small cohorts or anecdotal reports. Recently, a big randomized double-blind dose-response and comparative study revealed that an optimized dosage of 0,3 mg/kg was superior to other dosages and non-inferior to doxycycline as gold standard of systemic rosacea treatment and proved effective and safe in papulopustular and phymatous subtypes. However, the substance is still not licensed for this indication The efficacy of isotretinoin in rosacea is probably mainly related to anti-inflammatory mechanisms as well as anti-oxidative, anti-angiogenic and antifibrotic properties. The classical antiseborrheic effect of isotretinoin might play a role in special subtypes like the phymatous type or rosacea fulminans.