Pityriasis Versicolor: Symptoms, Causes, and Effective Treatment in the UK

Pityriasis versicolor, also known as tinea versicolor, is a common and benign fungal skin infection. It is characterised by the appearance of small, oval-shaped patches on the skin, which may be lighter (hypopigmented), darker (hyperpigmented), or pinker than the surrounding skin. These patches are caused by an overgrowth of Malassezia, a type of yeast that lives naturally on the surface of most adults' skin without causing any issues.

In the UK, the condition is particularly noticeable during the summer months or after holidays to warmer climates. This is because the yeast prevents the affected areas of skin from tanning, making the pale patches more prominent against sun-exposed skin. While the condition can affect people of any age, it is most frequently seen in teenagers and young adults, likely due to increased oil production on the skin during these years.

The most distinctive symptom of pityriasis versicolor is the change in skin pigmentation. These patches typically appear on the torso, back, chest, upper arms, and sometimes the neck. Face involvement is less common in adults but can occur in children.

Key characteristics of the patches include:

• Individual spots that may merge into larger patches over time.
• A slightly scaly or flaky surface, though this may only be visible if the skin is gently scraped.
• Patches that do not tan when exposed to sunlight.
• Occasional mild itching, particularly when the person becomes hot or sweaty.
• Varied colouration: white, pink, red, or brown.

It is important to note that pityriasis versicolor is not painful and does not cause permanent scarring. Because the yeast interferes with the normal pigmentation process, the colour difference often persists for several weeks or months even after the fungus has been successfully treated.

The yeast responsible for pityriasis versicolor, Malassezia, is a normal resident of healthy skin. It is not an infection caught from poor hygiene or contact with others. Problems only arise when the yeast begins to multiply uncontrollably. Several factors can trigger this overgrowth:

• Warm and Humid Environments: High temperatures and moisture encourage fungal growth.
• Oily Skin: The yeast thrives on skin oils (sebum).
• Hormonal Changes: This is why the condition is more prevalent during puberty and young adulthood.
• Weakened Immune System: People with suppressed immune systems may be more susceptible to overgrowth.
• Sweating: Excessive perspiration provides the moist environment the yeast prefers.

Because the cause is a naturally occurring yeast, pityriasis versicolor is not contagious. You cannot pass it to others through skin-to-skin contact, sharing towels, or using the same gym equipment.

In most cases, a GP or pharmacist can diagnose pityriasis versicolor simply by examining the appearance and distribution of the patches. The scale and colour of the spots are usually quite distinctive.

If there is any doubt, a clinician might use a Wood's lamp (a handheld ultraviolet light) which can cause the affected patches to glow a yellowish-green colour. In rare or persistent cases, a small skin scraping may be taken and sent to a laboratory for microscopic examination to confirm the presence of the yeast. This helps to rule out other skin conditions with similar appearances, such as vitiligo (which causes a complete loss of pigment and no scaling) or pityriasis alba.

Treating pityriasis versicolor involves using antifungal medication to reduce the Malassezia yeast to normal levels. The primary treatments used in the UK include:

• Antifungal Shampoos: Ketoconazole (Nizoral) or selenium sulphide (Selsun) shampoos are common first-line treatments. Despite being called shampoos, they are applied to the affected areas of the body, left on for 5–10 minutes, and then rinsed off. This is usually repeated daily for five to seven days.
• Antifungal Creams: For small, localised areas, antifungal creams like clotrimazole or terbinafine may be applied twice daily for several weeks.
• Oral Antifungals: If the rash covers a large area of the body or does not respond to topical treatments, a GP may prescribe antifungal tablets such as itraconazole or fluconazole. These are usually taken for a short period (1–7 days).

It is crucial to understand that while the treatment kills the fungus quickly, the skin colour will not return to normal immediately. It can take several months for the skin to re-pigment and for the patches to blend back in with the rest of your skin. This does not mean the treatment has failed.

Pityriasis versicolor has a high rate of recurrence, particularly in people who are prone to oily skin or those living in warm climates. Statistics suggest the condition returns in up to 80% of cases within two years.

To reduce the risk of the patches returning, you may be advised to:

• Use an antifungal shampoo as a body wash once every two to four weeks, particularly during the spring and summer months.
• Avoid using heavy, oily skin products or sun creams that can clog pores.
• Wear loose-fitting, breathable clothing (like cotton or linen) to reduce sweating.
• Dry your skin thoroughly after showering, especially in skin folds.

While pityriasis versicolor is harmless, it can be distressing for cosmetic reasons, and self-diagnosis is not always accurate. You should consult an online GP if:

• The patches are spreading rapidly or cover a significant portion of your body.
• Over-the-counter antifungal treatments from the pharmacy have not worked after several weeks.
• The patches are itchy, inflamed, or causing you emotional distress.
• The condition keeps recurring frequently despite preventative measures.

An online GP can review photos of your skin, confirm the diagnosis, and provide prescriptions for stronger antifungal treatments or oral medications if required.