Various conditions can lead to irritated, red skin. Causes can range from a temporary sensitivity to a chronic skin problem. Common culprits of red skin or red spots include: 1  Dry skin. 2  Sunburn. 3  Rosacea. 4  Acne. 5  Allergic contact dermatitis. 6  Eczema (atopic dermatitis).
Methylene blue is a component of a frequently prescribed urinary analgesic/anti-infective/anti-spasmodic known as Prosed, a combination of drugs which also contains phenyl salicylate, benzoic acid, hyoscyamine sulfate, and methenamine (aka hexamethylenetetramine and not to be confused with 'methanamine').
It has many uses in biology and chemistry; for example, it can be used as a stain and as a pharmaceutical drug. At room temperature it appears as a solid, odorless, dark green powder, that yields a blue solution when dissolved in water. The hydrated form has 3 molecules of water per molecule of methylene blue.