Can Mould Cause Hair Loss? Fungal Infections, Telogen Effluvium and What to Do

Does mould cause hair loss?#

Household mould does not directly cause hair loss. There is no NICE, MHRA, or NHS guidance classifying indoor mould exposure as a direct cause of hair shedding. That said, mould and hair loss do overlap in two real ways. First, fungal scalp infections (which belong to the same broad kingdom as mould) are a proven cause of patchy hair loss. Second, prolonged illness from mould exposure can trigger a type of shedding called telogen effluvium, where the body sheds hair in response to physical stress.

Understanding which of these applies to you makes a big difference to treatment.

Tinea capitis: the fungal infection that does cause hair loss#

Tinea capitis is a scalp ringworm infection caused by fungi called dermatophytes, specifically Trichophyton and Microsporum species. These are distinct from the black or green mould growing on damp walls, but they are fungi. The confusion is understandable.

In the UK, Trichophyton tonsurans is now the dominant strain in urban areas. It spreads person to person, which is why outbreaks occur in schools, shared housing, and families. A 17-year analysis of dermatophyte infections in South-East England found tinea capitis to be the most common scalp fungal condition seen in secondary care.

What it looks like#

Tinea capitis typically causes:

• Patchy, scaly bald spots, often with broken hairs at the scalp surface
• Itching, redness, and dandruff-like flaking
• In more severe cases, a kerion (a painful, boggy swelling that can scar)
• Occasionally swollen lymph nodes at the back of the neck

It can resemble alopecia areata or seborrhoeic dermatitis, so a GP will often confirm the diagnosis with a scalp scraping (sent to a lab to identify the fungal species) or by using a Wood's lamp, which causes Microsporum species to fluoresce blue-green under UV light. Trichophyton tonsurans does not fluoresce, so a lab culture is the reliable test.

Who gets it#

Children aged 3 to 14 are most commonly affected, but adults living in crowded conditions, immunocompromised individuals, and people sharing hairbrushes or hats are also at risk. According to UKHSA guidance, children with tinea capitis do not need to be excluded from school once treatment has started, which is reassuring for parents.

How mould exposure can trigger hair shedding indirectly#

Prolonged exposure to damp, mouldy homes is associated with respiratory illness, allergic reactions, and chronic low-grade stress on the body. Any significant physical illness can push hair follicles into a resting phase called telogen. Around 2 to 4 months later, those hairs shed at once, producing noticeable thinning across the scalp. This is telogen effluvium.

The mechanism is the same whether the trigger is a chest infection, a prolonged bout of sinusitis from mould allergy, or any other systemic stressor. The shedding itself is not from a scalp problem; it reflects what the body went through weeks earlier.

As for mycotoxins, the toxic compounds produced by species such as Stachybotrys chartarum (sometimes called black mould), evidence linking them to hair loss in humans is limited to case reports and animal studies. No well-designed clinical trials have established a direct causal link.

A comparison of the three patterns#

Treatment for tinea capitis on the NHS#

Topical creams alone do not penetrate the hair follicle, so oral antifungals are required.

For Trichophyton (the dominant UK strain), terbinafine is now the preferred first-line treatment under current NICE CKS guidance. In children, dosing is based on weight: 62.5 mg daily for children under 20 kg, 125 mg daily for 20 to 40 kg, and 250 mg daily for those over 40 kg. It is important to note that terbinafine is not licensed for use in children under 12 years (and, for some indications, under 18) in the UK, meaning its use in younger children is off-label. NICE CKS also recommends seeking specialist advice before treating children under 1 year. A typical course lasts 4 to 8 weeks. Adults are generally prescribed 250 mg daily.

Griseofulvin remains the treatment of choice for Microsporum infections or where terbinafine is contraindicated. It requires a longer course (8 to 12 weeks or more) and must be taken with a fatty meal for absorption. Note that griseofulvin is not licensed in the UK for children under 1 year, and supply has at times been intermittently restricted; your prescriber or pharmacist will be able to advise on current availability.

Regarding shampoos: antifungal shampoos are sometimes used alongside oral treatment to reduce spore shedding and limit spread to others, but they do not cure the infection on their own and should not replace oral therapy. A pharmacist can advise on adjunct options available without a prescription.

Hair regrowth after treatment#

For most people, hair grows back fully once the infection clears, provided treatment starts before scarring occurs. A kerion left untreated can cause permanent scarring alopecia, where follicles are destroyed. This is why early diagnosis matters.

Telogen effluvium from mould-related illness generally resolves completely once the trigger is removed. Expect shedding to stop within a few months of the body recovering, with visible regrowth over 6 to 12 months.

Your housing rights if mould is affecting your health#

If you rent your home and mould is contributing to health problems, UK law gives you specific protections.

The Homes (Fitness for Human Habitation) Act 2018 gives tenants the right to take legal action if a property is unfit to live in, with damp and mould listed as qualifying hazards. Awaab's Law, introduced through the Social Housing Regulation Act 2023, adds further requirements for social housing landlords, with specific investigation and repair timescales set out in the associated statutory instrument. Your local council's environmental health team can inspect private rented properties and issue improvement notices under the Housing Health and Safety Rating System.

Documenting the mould with dated photographs and raising the issue in writing to your landlord creates a paper trail if you need to escalate.

When to speak to a pharmacist or GP#

See your GP if you or your child has patchy scalp hair loss with scaling or itching, as this warrants a scraping or culture to rule out tinea capitis. Unexplained diffuse shedding after a period of illness also merits review. A GP may refer to NHS dermatology if the diagnosis is unclear or the infection is not responding to first-line treatment (ICB referral criteria apply). If you are unsure whether your scalp symptoms need a prescription, your pharmacist is a good first call for advice.

For men experiencing male pattern hair loss separate from these conditions, Totiva's hair loss service offers online consultations with UK clinicians for treatments including finasteride and minoxidil. The consultation is free, and you pay only if treatment is approved. Women with hair loss should speak to their GP, as Totiva's hair loss service is for men only. You can start a consultation at Totiva if you think male pattern baldness is part of the picture.