Rosacea is not just a physical condition. Left untreated, it can progress and possibly cause scarring, which can have physical and psychological impacts. Rosacea has three stages, and with each stage symptom severity increases.

Mild This stage usually begins with nothing more than a blush or a sunburned look. The erythema can persists for hours or days. Soon the redness becomes more noticeable and doesn't go away.

Moderate As a result of the continual flushing, the skin becomes irritated and inflamed. Pimples may appear on the face. These pimples may be papules (small, red and solid) or pustules (pus-filled, like teenage acne).

Severe This stage is often called inflammatory rosacea. As the condition progresses, papules and pustules crop up and may continue for weeks. These lesions usually appear on the forehead, nose and cheeks.Facial pores become more prominent.

The following adverse experiences have been reported with the topical treatment of metronidazole: burning, skin irritation, dryness, transient redness, metallic taste, tingling or numbness of extremities and nausea.