Few things in life are quite as aggravating as an unrelenting itch. Itching was once thought to be a type of pain, but the Stanford School of Medicine explains that itchy sensations are conducted by a specific type of nerve cell that is separate from pain conducting nerve cells. When itching affects the feet, the result can be particularly maddening. A variety of factors can cause itchy feet.
Fungal Infections
The warm moist environment of a gym shoe can provide the perfect breeding ground for fungal infections. Tinea pedis results when a dermatophyte fungus breeds in the folds of the foot skin, causing various types of itchy skin reactions.
Athletes' foot is a form of Tinea pedis that causes skin between the toes to peel. Ringworm fungus can cause round dry lesions on the top of the foot, according to the University of Maryland Medical Center.
Eczema
Eczema is a form of dermatitis, or skin inflammation that can affect the feet. It can be of the discoid variety, meaning it manifests as round red patches with a dry, crusty surface. Eczema can cause severe itch, or in some cases none at all according to DermNet NZ.
Contact Dermatitis
The skin of the foot sometimes comes into contact with substances that the immune system mistakenly identifies as a threat. The result is an allergic response that can manifest as an itchy rash. Skin irritations due to contact with an allergen or irritant are referred to as contact dermatitis. Perhaps the most commonly recognized form of contact dermatitis is that which results due to exposure to poison ivy. Other common allergens that can cause skin rashes on the feet include latex, such as found in rubber soled shoes and sock elastic, and nickel metal, which is commonly used in costume jewelry.
Frostbite
Exposure to extreme cold can cause body fluids to freeze and crystallize, damaging blood vessels and depriving body tissues of oxygen, a condition commonly known as frostbite. The feet are particularly vulnerable to frost bite, being the appendage that is furthest from the warm trunk of the body. When the initial effects of frostbite set in, the skin can feel itchy and swollen, according to the McKinley Health Center at the University of Illinois.
Chilblains are itchy red bumps that result from vasculitis caused by cold. Several hours after cold exposure, the rewarming of chilled arteries causes them to expand and leak blood into the tissues, according to DermNet NZ, causing swelling and an itchy sensation.
