<unk>  is inflammation of the skin, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can vary from small to covering the entire body.<unk>  is often called eczema, and the difference between those terms is not standardized. The exact cause of the condition is often unclear. Cases may involve a combination of allergy and poor venous return. The type of<unk>  is generally determined by the person's history and the location of the rash. For example, irritant<unk>  often occurs on the hands of those who frequently get them wet. Allergic contact<unk>  occurs upon exposure to an allergen, causing a hypersensitivity reaction in the skin. Prevention of atopic<unk>  is typically with essential fatty acids, and may be treated with moisturizers and steroid creams. The steroid creams should generally be of mid- to high strength and used for less than two weeks at a time, as side effects can occur. Antibiotics may be required if there are signs of skin infection. Contact<unk>  is typically treated by avoiding the allergen or irritant. Antihistamines may help with sleep and decrease nighttime scratching.<unk>  was estimated to affect 245 million people globally in 2015, or 3.34% of the world population. Atopic<unk>  is the most common type and generally starts in childhood. In the United States, it affects about 10–30% of people. Contact<unk>  is twice as common in females as males. Allergic contact<unk>  affects about 7% of people at some point in their lives. Irritant contact<unk>  is common, especially among people with certain occupations; exact rates are unclear.
Dermatitis
Psoriasis
Photokeratitis
Scabies
Keratitis
Dermatitis herpetiformis
Arthralgia
Lichen simplex chronicus