Pityriasis Versicolor and Pityriasis Rosea – How Do They Differ from Dandruff?

Pityriasis versicolor and pityriasis rosea share part of their name with the medical term for dandruff (pityriasis capitis), but they are separate conditions. Pityriasis versicolor is a superficial skin infection caused by Malassezia yeasts, showing up as discoloured patches on the trunk, while pityriasis rosea is a self-limiting rash that is probably viral in origin. Both should be diagnosed by a doctor, and skincare products can only support skin care and help ease symptoms. Here we explain how to recognise them and how they differ from ordinary dandruff and scalp ringworm.

What is pityriasis versicolor?

Pityriasis versicolor (also known as tinea versicolor) is a superficial skin infection caused by yeasts of the Malassezia genus (mainly M. globosa and M. furfur), which live naturally on human skin [1,2]. Under favourable conditions – heat, humidity, heavy sweating or oily skin – the yeasts switch to a form that causes skin changes. Pityriasis versicolor most often affects teenagers and young adults, and it thrives in warm, humid conditions.

Pityriasis versicolor – symptoms and what it looks like

Pityriasis versicolor appears as well-defined patches that may be lighter, darker or pinkish-brown compared with the surrounding skin – hence the name “versicolor”, meaning “of varying colours”. What does pityriasis versicolor look like?

• the patches are oval and often merge into larger areas,
• fine scaling becomes more visible when the skin is rubbed,
• the patches usually don’t itch, or itch only slightly,
• they become more noticeable after sun exposure, as the lighter patches do not tan [2].

Pityriasis versicolor on the scalp and body

On the body, pityriasis versicolor most often appears on the back, chest, upper arms and neck – areas rich in sebaceous glands. Pityriasis versicolor on the scalp is rare, although Malassezia can live there too.

What is pityriasis rosea?

Pityriasis rosea (sometimes called Gibert’s pityriasis) is an acute, self-limiting skin condition whose cause is not fully understood; it is thought to be linked to the reactivation of the HHV-6 and HHV-7 viruses [3]. It mainly affects children, teenagers and young adults, is more common in the colder months, and usually clears up on its own within a few weeks [4,5].

Symptoms of pityriasis rosea

Pityriasis rosea follows a characteristic course:

• first, a single larger, oval pink patch with a collar of scaling appears – the so-called herald patch,
• after about 1–2 weeks, numerous smaller oval patches appear on the trunk and upper arms, following the skin’s natural lines – on the back they form a pattern resembling a Christmas tree,
• the patches may be mildly itchy,
• the rash is sometimes preceded by cold-like symptoms [3,4].

Pityriasis versicolor, pityriasis rosea and ordinary dandruff – how do they differ?

Pityriasis versicolor, pityriasis rosea and ordinary dandruff differ in their cause, location and management. All they really have in common is part of the name and flaking skin.

Scalp ringworm – how to recognise it?

Scalp ringworm (tinea capitis) is a contagious fungal infection of the hair and scalp that mainly affects children aged 3–7 [6]. In studies, one of the dominant causes was the fungus Microsporum canis, which is passed on by cats and dogs [7]. Scalp ringworm can resemble ordinary dandruff, but the following signs and details from the patient’s history may point to it:

• round, scaly patches with thinning hair or hairs broken off close to the skin,
• black dots where the hairs have broken off,
• redness and itching, and in inflammatory forms also pustules or other marked inflammation; the nearby lymph nodes may also be swollen,
• cases in several members of the household or contact with an animal.

Scalp ringworm cannot be treated with shampoos alone – it requires oral antifungal treatment prescribed by a doctor [6,8]. Antifungal shampoos may be used alongside this treatment [6,8].

Treatment and care – when are medicines needed and when do dermocosmetics help?

Pityriasis versicolor, pityriasis rosea and scalp ringworm are conditions that need a proper diagnosis and appropriate management. Dermocosmetics can support skin care and help relieve some symptoms, but they cannot replace treatment when it is needed.

• Pityriasis versicolor is treated mainly with topical antifungals (e.g. containing ketoconazole, clotrimazole or selenium sulphide), and in extensive or stubborn cases with oral medication [1,2]. Topical antifungals, including creams and shampoos, should be used as directed for the specific product or as advised by a doctor or pharmacist. Discolouration may persist for several weeks or months after treatment – this does not mean the infection is still active.
• Pityriasis rosea usually needs no treatment of the cause. A doctor may recommend products to relieve itching and, in more severe cases, other treatment [4]. Pregnant women with symptoms of pityriasis rosea should see a doctor [3].
• Scalp ringworm requires oral treatment, with an antifungal shampoo used as an add-on [8].

Dermocosmetics can support everyday skin care and help keep the skin comfortable, but their role depends on the type of skin problem. For ordinary scalp dandruff, a well-chosen anti-dandruff shampoo can help, such as CAPILARTE Anti-Dandruff Shampoo with clotrimazole and piroctone olamine. You can read more about choosing the right product in our guide on how to choose a dandruff shampoo.

Read also: Scalp Seborrhea – What Causes It and How Can You Effectively Restore Balance?

FAQ – frequently asked questions about pityriasis versicolor and pityriasis rosea

Is pityriasis versicolor contagious?

No, pityriasis versicolor is not contagious. The Malassezia yeasts that cause it live naturally on everyone’s skin, and the condition develops under favourable conditions such as heat, humidity and sweating [2].

Does pityriasis rosea go away on its own?

Yes, pityriasis rosea usually goes away on its own, most often within a few weeks [4,5]. It rarely comes back. Because other skin conditions can look similar, the diagnosis should always be confirmed by a doctor.

How should you care for your skin after treating pityriasis versicolor?

After treating pityriasis versicolor, it’s worth limiting the factors that encourage it to return: wear breathable clothing, change out of sweaty clothes quickly and avoid rich, heavy products on the skin of your trunk. Pityriasis versicolor often recurs, so a doctor may recommend washing the skin with an antifungal product as a preventive measure, e.g. once a month, especially before summer [2]. The lighter patches will even out gradually – sun protection for the whole body helps with this.

This article is for educational purposes only and does not replace medical advice. New patches, a rash or scaly patches on the scalp should be assessed by a dermatologist.

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