According to WebMD, untreated ringworm infections can lead to blistering and cracked skin, which in turn can become infected with bacteria. Bacterial infections must be treated with antibiotics. In most cases, ringworm infections can be treated with over-the-counter medications. If non-prescription methods do not work, ringworm can also be treated with prescription medications that are designed to kill the fungus.
Healthline explains that the most common symptoms of ringworm of the scalp are itching patches and broken sections of hair. When the hair breaks off, scaly red patches or bald spots appear. If ringworm of the scalp is left untreated, the bald spots and patches can increase. Individuals with untreated ringworm of the scalp are also at risk for developing kerion, swellings on the scalp that crust over and drain pus.
According to Medline Plus, ringworm is a common infection among children, but adults can develop the infection as well. Contrary to popular belief, ringworm is not actually a worm, but a fungus. Ringworm patches tend to be red around the outside and flesh-colored in the center, taking on a ring-like appearance. Ringworm is easily spread from person to person and the fungus tends to thrive in moist areas. Ringworm can appear anywhere on the skin and nails. Untreated ringworm infections of the nails can lead to discoloration and crumbling.