INTRODUCTION
Rosacea is a chronic inflammatory cutaneous vascular disorder involving the central nervous system that presents various signs and symptoms, including central facial erythema, flushing, edema, papulopustular lesions, and telangiectasias.1 It affects approximately 16 million people in the United States, with individuals with fair sun-sensitive skin (skin phototypes I and II) being at the greatest risk for developing this condition2; however, it is also underdiagnosed in patients with skin of color because of clinicians' poor ability to detect erythema in darker skin individuals.3 Although the pathogenesis of rosacea is unknown, it is hypothesized to be multifactorial, involving both genetic and environmental factors that result in the dysfunction of both nervous and vascular elements.4 It has been speculated that the vasodilation, increase in cutaneous blood flow, and thermal hypersensitivity seen in individuals with rosacea may be explained by stimulation of transient receptor potential (TRP) receptors and release of neuropeptides in response to chemical, mechanical, and thermal stimuli.1
Rosacea has been traditionally divided into 4 subtypes – "classic type" erythematotelangiectatic (ETR), papulopustular (PPR), phymatous, and ocular rosacea5 although patients can present with overlapping phenotypes. ETR is characterized by flushing episodes persisting for greater than 10 minutes, and it is frequently associated with burning and stinging. PPR involves central facial redness with small papules topped with pustules. Phymatous rosacea describes skin thickening and irregular surface nodularities, often involving the nose (rhinophyma), chin (gnathophyma), and forehead (metophyma).5 Ocular rosacea includes eye erythema, pruritus, burning, and photophobia.6
Neurogenic rosacea is a recently proposed new subtype that describes rosacea patients who have prominent and debilitating neurologic and neuropsychiatric symptoms.5 There is no professional consensus on the definition for neurogenic rosacea and it has yet to be further elucidated. The common denominator for patients with neurogenic rosacea is the experience of neuronal rosacea symptoms (eg, burning and
