Erythema is characterized by the reddening of the skin, the appearance of the rash. Erythema is caused due to injury or irritation is caused to blood capillaries. Different types of erythemas include photosensitive erythema, erythema multiform and erythema nodusum. In multiform erythema the symptoms are sports or lesions, fever, itchy skin, joint aches, general ill feeling and for nodusum erythema the symptoms are reddish, painful and tender lumps appear usually on the legs below the knees. Erythema journals deals with reddening of skin and rashs.