Symptoms
Athlete's foot usually causes a scaly red rash. The rash typically begins in between the toes. Itching is often the worst right after you take off your shoes and socks.
Some types of athlete's foot feature blisters or ulcers. The moccasin variety of athlete's foot causes chronic dryness and scaling on the soles that extends up the side of the foot. It can be mistaken for eczema or even as dry skin.
The infection can affect one or both feet and can spread to your hand â especially if you scratch or pick at the infected parts of your feet.
When to see a doctor
If you have a rash on your foot that doesn't improve after self-treatment, see your doctor.
If you have diabetes, see your doctor if you suspect you have athlete's foot, especially if you notice any signs of a possible secondary bacterial infection such as excessive redness, swelling, drainage or fever.
Source: http://www.mayoclinic.com