Ringworm of the scalp is not really a worm, but a fungal infection. It gets the name “ringworm” because the fungus makes circular marks on the skin, often with flat centers and raised borders. Also called Tinea capitis, this infection affects your scalp and hair shafts, causing small patches of itchy, scaly.
Ringworm is a highly contagious infection that’s usually spread through person-to-person contact or by sharing combs, towels, hats, or pillows. Ringworm is most common in children, but can infect a person of any age.
Fungi called dermatophytes cause ringworm of the scalp. Fungi are organisms that thrive on dead tissue, such as fingernails, hair, and the outer layers of your skin.
Ringworm spreads easily, especially among children. You can get ringworm from touching the skin of an infected person. If you use combs, bedding, or other objects that have been used by an infected person, you’re also at risk.
House pets, such as cats and dogs, can also spread ringworm. Farm animals like goats, cows, horses, and pigs can be carriers too. These animals might not show any signs of infection.
Overcrowding and poor hygiene increase the spread of ringworm. Dermatophytes prefer warmth and moisture, so they thrive on sweaty skin.
The most common symptom of ringworm is itchy patches on the scalp. Sections of hair may break off at or close to the scalp, leaving scaly, red areas or bald spots. You may see black dots where the hair has broken off. Left untreated, these areas gradually grow and spread.
Other symptoms include:
- brittle hair
- painful scalp
- swollen lymph nodes (glands that help the body fight off infection)
- low-grade fever
In more severe cases, you may develop kerion, crusty swellings that drain pus. These can lead to permanent bald spots and scarring.
A visual exam is often enough for a doctor to diagnose ringworm of the scalp. Your doctor may use a special light called a Wood’s lamp to illuminate your scalp and determine signs of infection.
Your doctor may also take a skin or hair sample to confirm the diagnosis. This involves taking a hair or scraping from a scaly patch of scalp and looking at it under a microscope. The sample is then sent to a lab to determine the presence of fungi. This process may take up to three weeks.
Your doctor will probably prescribe fungi-killing oral medication and medicated shampoo.
The leading antifungal medications for ringworm are griseofulvin and terbinafine hydrochloride. Both are oral medications that you take for approximately six weeks. Both have common side effects, including diarrhea and upset stomach. Your doctor may recommend taking these medications with a high-fat food like peanut butter or ice cream.
Other possible side effects of griseofulvin (sold as Grifulvin V, Gris-PEG) include:
- sun sensitivity
- faintness or dizziness
- allergic reactions (in people who are also allergic to Penicillin)
- rash or hives
Other possible side effects of terbinafine hydrochloride (sold as Lamisil) include:
- stomach pain
- rash or hives
- loss of taste or change in taste
- allergic reaction
- in rare cases, liver problems
Your doctor may prescribe a medicated shampoo to remove fungus and prevent the spread of infection. The shampoo will contain the active antifungal ingredients ketoconazole or at least 2.5 percent selenium sulfide. Leave the shampoo on for five minutes, then rinse.
Your doctor may tell you to use this shampoo a couple of times a week for a month. Medicated shampoo helps prevent the fungus from spreading, but doesn’t kill ringworm. You must combine this type of treatment with oral medication.
Recovery and Prevention of Reinfection | Outlook
Ringworm heals very slowly. It can take more than a month to see any improvement. Be patient and continue taking all medication as directed. Your doctor may want to check you or your child in four to six weeks to make sure the infection is clearing.
Your child can usually return to school once they start treatment for ringworm, but ask your doctor when it’s safe for them to return.
Pets and other family members should be examined and treated if necessary. This will help prevent reinfection. Do not share towels, combs, hats, or other personal items with other family members. You can sterilize combs and brushes that belong to the infected person by soaking them in bleach water.
It’s hard to get rid of ringworm. It’s also possible to get the infection more than once. However, recurrences often stop at puberty. Long-term effects include possible bald patches or scarring.
The dermatophytes that cause ringworm are common and contagious. This makes prevention difficult. Since children are especially susceptible, tell your children about the risks of sharing hairbrushes and other personal items. Regular shampooing, hand washing, and other normal hygiene routines can help prevent the spread of infection.
It can be hard to tell if an animal has ringworm, but a common sign of infection is bald patches. Avoid petting any animals that have patches of skin showing through their fur. Maintain regular checkups for all pets and ask your veterinarian to check for ringworm.