Basically there are seven differences between acne and rosacea:
(1) Rosacea does not usually present itself with blackheads (comedo formations) that are seen with acne vulgaris.
(2) Acne usually presents itself with plugging of the ducts of the oil glands, resulting in blackheads and pimples on the face and sometimes also the back, shoulders or chest. Rosacea seems to be linked to the vascular network of the central facial skin and causes redness, bumps, pimples and other symptoms that rarely goes beyond the face.
(3) The age of onset, and the location of redness is a clue. Rosacea is commonly an adult disease, and is generally restricted to the nose, cheeks, chin and forehead. However, young ones have been diagnosed with rosacea. Also, one report “indicated that some people who have rosacea do not have it on their face at all, but rather on their back or elsewhere”11 which adds to the confusion.
(4) Rosacea is usually accompanied with frequent flushing and a persistent redness while acne vulgaris usually doesn’t present itself with flushing.12 However not all report frequent flushing and flush no more than the general population.13
(5) Acne treatments tend to aggravate rosacea leading to a diagnosis of rosacea. Common treatments for acne such as Salicylic Acid, Glycolic Acid, Tretinoin, Retin-A Micro, Avita, Differin, Benzoyl Peroxide, Azelaic Acid, Triclosan, Acne peels, Chemical peels, Topical exfoliants, Toners, Astringents, Witch Hazel and Alcohol tend to aggravate rosacea (but not always). Rosacea sufferers have extremely sensitive skin. Therefore, when a patient doesn’t respond to acne treatment and the acne treatment aggravates the
condition it may be diagnosed as rosacea.
(6) Eye symptoms are not associated with acne, so a careful examination for eye symptoms or a finding of ocular pathology will help confirm the diagnosis of rosacea. 50% of rosaceans have ocular rosacea.
(7) Unlike acne, rosacea is not driven forward by Propionibacterium , and subsequently should not be treated using acne medications. However, to add more confusion there is a theory that P. acnes may be a potential aggravating factor in rosacea.
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