Ringworm bald spots on the scalp are almost always temporary. The fungus that causes scalp ringworm (tinea capitis) invades the hair shaft and makes it brittle, causing hairs to snap off near the surface. But in most cases, it doesn’t destroy the hair follicle itself. Once the infection is treated, hair typically grows back within 6 to 12 months.
There is one important exception: a severe inflammatory reaction called a kerion can cause permanent scarring. Understanding the difference between routine ringworm and a kerion is the key to knowing whether your hair loss will resolve.
How Ringworm Causes Hair to Fall Out
The fungi responsible for scalp ringworm feed on keratin, the protein that makes up your hair and outer skin. After landing on the scalp, fungal threads spread outward through the top layer of skin and grow downward into the hair, invading keratin as it forms. By the second week, infected hair becomes visible above the surface. By the third week, those hairs are brittle enough to snap off.
Depending on the type of fungus, the hair breaks in slightly different ways. Some species grow on the outside of the hair shaft, destroying its protective outer layer. Others grow inside the shaft, causing hairs to break right at the scalp surface and leave behind tiny dark stubs, sometimes called “black dots.” Either way, the result is patchy hair loss that looks alarming but is largely mechanical: the hair is breaking, not falling out from a dead root.
When Hair Loss Becomes Permanent
The real risk for lasting damage comes from a kerion, which is the body’s intense inflammatory overreaction to the fungus. A kerion looks dramatically different from a typical ringworm patch. Instead of a dry, scaly spot, you’ll see a boggy, swollen mass on the scalp that’s painful, red, and often oozing pus. It can feel spongy to the touch and may be covered in thick crusts with matted hair stuck to them.
A study of 80 pediatric patients with kerions found that 27.5% developed permanent hair loss in the affected area. That means roughly one in four people with this severe form end up with scarring that prevents hair from regrowing. The scarring happens because the intense inflammation destroys the hair follicles themselves, not just the hair shafts. Once a follicle is replaced by scar tissue, it can no longer produce hair.
Another rare but severe form called favus, caused by a different species of fungus, produces distinctive yellow cup-shaped crusts around hair follicles. This chronic infection can also destroy follicles and pilosebaceous structures, leading to scarring alopecia if left untreated.
Signs That Point Toward Scarring
A standard ringworm patch starts as small red bumps that progress into grayish, ring-shaped scaly areas. This is the common presentation and carries very low risk of permanent loss. The warning signs that scarring may develop include:
- Boggy, spongy swelling rather than a flat patch
- Pus draining from multiple spots across the affected area
- Thick crusting and matted hair stuck together with discharge
- Significant pain and tenderness in the area
- Swollen lymph nodes near the neck or behind the ears
If you notice any of these, the infection has likely progressed to a kerion or another deeply inflammatory stage. Early treatment at this point matters more than at any other time. In the kerion study, patients who ended up with permanent hair loss had actually presented to their clinic about a month earlier on average than those who recovered fully, suggesting that the severity of the individual immune response plays a significant role alongside timing.
How Scalp Ringworm Is Treated
Scalp ringworm requires oral antifungal medication. Topical creams alone cannot reach the fungus inside the hair shaft and follicle. The most commonly prescribed options work by stopping the fungus from growing or killing it outright, and treatment typically lasts 4 to 12 weeks depending on the specific medication and the type of fungus involved. Treatment usually continues for at least 2 weeks after visible symptoms have cleared to make sure the infection is fully gone.
For severe cases with significant inflammation or a kerion, a short course of oral steroids is often added alongside the antifungal. The steroid is tapered over about 2 weeks and serves to calm the immune overreaction, reduce swelling, ease pain, and potentially lower the chance of permanent scarring. This combination approach targets both the infection and the body’s own damaging inflammatory response.
What Regrowth Looks Like
After completing treatment for uncomplicated ringworm, don’t expect hair to bounce back immediately. The scalp needs time to recover, and new hair growth is slow. Most people see their bald spots fill in over 6 to 12 months. The new hair may initially look finer or lighter than surrounding hair before gradually returning to its normal texture and color.
During this window, the scalp where the patches were may still look slightly different in color or texture. This is normal healing and not a sign of scarring. True scarring alopecia looks distinctly different: the skin in the affected area appears smooth, shiny, and slightly pale or discolored, with no fine hairs emerging at all. If you’re several months past treatment and see even short, fine hairs growing in the patch, the follicles are alive and recovery is on track.
For the roughly three-quarters of kerion patients whose hair does grow back, the timeline may be longer and the initial regrowth patchier, but the follicles that survived the inflammation will eventually produce normal hair again.