Accutane has been known to cause blushing which usually resolves after treatment. It is not known the exact reason for this although some authorities feel Accutane can cause a mild increase in vasculature, much like its cousin tretinoin. ( It is considered a good thing there, however.)
Accutane can cause increased redness to the skin due to its possible photosensitivity potential. The dryness which Accutane creates by diminishing the size and excretory quality of the sebaceous glands, makes the skin more susceptible to the elements. Thus, wind and cold weather can lead to redness when prior to Accutane the skin's natural oils would provide a protective sheet.
You might return to our dermatologist or family physician for an evaluation to ensure that you do not have Rosacea. Does your face have the tell-tale fine blood vessels (telangiectasias) of this condition?
One must also consider the carcinoid syndrome with continuous blushing especially if the blushing is accompanied by diarrhea, wheezing or dry skin. Carcinoid tumors can be benign or malignant and are derived from what termed enterochromaffin cells. These cells secrete a variety of agents such as serotonin and histamine. It is these agents that cause the flushing and blushing ascribe to this fascinating but sometimes deadly tumor.
You should use one of the over-the-counter products like Eucerin Redness Relief Clinique'sRedness Solutions or RevaleSkin. These will all help with the redness. IPL (intense pulsed light) would also be of much benefit.
Incidentally, a year on Accutane seems to me excessive.