Fungal infections
Fungal infections of the skin most commonly affect the feet, groin, scalp, or nails. Fungi grow best in warm, moist areas of the skin such as between toes, in the groin area, and under breasts. If infection occurs in an area where hair grows, such as the scalp, hair loss may occur.

Athlete's foot (tinea pedis) is the most common fungal skin infection. Symptoms include intense itching, cracks, blisters, redness, and scaling on the soles of the feet, and peeling, moist areas between the toes. It often recurs and must be treated again each time.

Jock itch (tinea cruris) causes redness, scaling, severe itching, and moistness on the skin of the groin and upper thighs. There are usually red, scaly, raised areas on the skin that weep or ooze pus or clear fluid.

Fungal nail infections cause discoloration, thickening, and often softening of the fingernails and toenails. Often a build-up of yellow debris develops under the free edge of the nail. These infections are difficult to treat and often cause permanent damage to the nails. If treatment with medication does not work, the nail may have to be removed. Some other infections cause inflammation of the nail bed or
the tissue adjacent to the nail. Without treatment, these can lead to serious complications, including more widespread infection.

Prevention
Keep feet clean and dry. Dry between the toes after swimming or bathing, and apply absorbent powder (Micatin, Zeasorb). 
Wear leather shoes or sandals that allow your feet to "breathe" and wear cotton socks to absorb sweat. 
Use powder on your feet and in your shoes. 
Give shoes 24 hours to dry between wearings. 
Do not go barefoot in public pools and showers. Wear thongs or shower sandals. 
Wash and dry the groin area well, especially after exercise, and apply powder to absorb moisture. 
Wear cotton underclothes and avoid tight pants and pantyhose. 
Don't share hats, shoes, combs, or hairbrushes.


Home Treatment
Follow the prevention guidelines above. 
For athlete's foot and jock itch, use an over-the-counter antifungal powder or lotion such as Lotrimin AF or Micatin. Use the medication for a week or two after the symptoms clear up to prevent recurrence. Do not use hydrocortisone on a fungal infection. 
Consider wearing cotton socks, and change them twice a day to keep your feet dry.
If possible, wear open sandals. When indoors, go in stocking feet.


When to Call a Health Professional
If signs of infection are present: increased swelling and redness, pus, or a honey-colored crust on the rash. 
If you have diabetes and develop athlete's foot. People with diabetes are at increased risk of infection and may need professional care. 
If home treatment fails to clear up athlete's foot or jock itch after two weeks. 
If there is sudden hair loss associated with flaking, broken hairs, and inflammation of the scalp; or if several household members suddenly start losing their hair.