Pityriasis rosea: symptoms, causes & treatment

Pityriasis rosea is a temporary skin disorder whose exact cause is not yet fully known. It is a self-limiting condition, which means it will go away on its own without treatment. The name refers to the peeling and pink color of the skin spots.

The condition is not harmful to your health and is not a sign of an underlying serious problem. It leaves no permanent traces. It is relatively common, especially during certain seasons it seems to be more common. Dermatologists see it regularly in their practice.

Some researchers believe that pityriasis rosea is a response to a viral infection. There are indications that certain viruses, such as certain types of the human herpes virus, may play a role. However, this has not been conclusively proven. What is certain: the rash itself is not contagious. You cannot pass it on to others, even through direct skin contact.

The disorder primarily affects adolescents and young adults between the ages of 10 and 35, although in principle it can occur at any age. Women seem to be affected slightly more often than men.

The development of pityriasis rosea usually follows a predictable pattern. Most experts believe it is triggered by a viral infection. Some report feeling unwell a few days before the rash appears, with mild flu-like symptoms such as tiredness or mild sore throat. This could indicate a viral infection that triggers the body to respond with a skin reaction.

There are indications that certain types of the human herpes virus, specifically HHV-6 and HHV-7, may be involved. These viruses are very common and most people have contracted them at some point without knowing it. In some, reactivation of these viruses could potentially trigger the skin response. However, not all researchers agree on this.

The mechanism behind the development has to do with an inflammatory response in the skin. Your immune system responds to something, possibly a virus, and this response leads to inflammatory cells that accumulate in certain layers of skin. This causes the pink discoloration. At the same time, the production of new skin cells accelerates, which leads to peeling.

It is striking that pityriasis rosea usually seems to occur more frequently in spring and autumn. This seasonal pattern supports the theory that a virus plays a role. However, the disorder can occur at any time.

It is important to emphasize that pityriasis rosea is not caused by poor hygiene, allergies, or other external factors that you can influence. It is not a bacterial or fungal infection. The rash itself is not contagious. There does not appear to be a genetic component and there are no obvious risk factors other than age.

Pityriasis rosea has a very characteristic appearance. The condition almost always starts with what is called the birthmark. This is a single, conspicuous patch of skin that usually appears on the chest, back, or abdomen. This first spot is larger than the later spots, usually between 2 and 5 centimetres. This mole has a pink scaly edge with a lighter, often skin-coloured core.

After the mole appears, it usually takes one to two weeks for the rest of the rash to develop. Then suddenly many smaller pink spots appear that are symmetrically distributed across your body. These spots are sharply defined and have a fine peeling, especially at the edges.

A remarkable feature is how the spots are arranged. They follow natural skin lines. On your back, they follow the direction of your ribs, making the pattern look like the branches of a Christmas tree. This specific arrangement is so characteristic that doctors often immediately think of pityriasis rosea.

The spots mainly appear on your torso: chest, stomach, back and sometimes upper arms and thighs. What's remarkable: your palms and soles are almost always spared. Your face is usually not affected either.

Itching occurs in some people, but not in everyone. The itching can get worse when you get warm, for example after showering or exercising. In general, you don't feel sick with pityriasis rosea.

The typical course is that the rash reaches its peak after about two to three weeks. After that, it slowly starts to improve. The spots gradually become paler and the peeling decreases. Eventually, they disappear altogether, usually within six to eight weeks. During and after healing, pigment differences may temporarily be visible, but these gradually disappear on their own.

Pityriasis rosea has a clear preference pattern. The mole, which appears first, usually occurs on the upper part of your torso. This typically means on your chest, between your shoulder blades, on your back, or on your stomach. Sometimes this first spot also appears on your shoulder or upper arm.

When the secondary rash appears, the many smaller spots that occur one to two weeks after the mole, they also mainly concentrate on your torso. Your chest and stomach in the front and your back back are the most affected areas. The distribution is usually symmetrical.

Your upper arms and thighs may also be affected, but usually to a lesser extent than your torso. The spots here are often less numerous and may appear a little later. They also follow the pattern of the skin lines.

A remarkable feature is that certain parts of the body are almost always spared. Your palms and soles are almost never affected. This is an important distinguishing feature. Your face also usually remains completely free of blemishes. This is a relief for many patients.

The Christmas tree pattern on the back is particularly characteristic. The spots lie in lines that run diagonally down from your spine, in the direction of your ribs. This creates a pattern that looks like the branches of an inverted Christmas tree.

The good news is that pityriasis rosea does not require treatment in most cases. The condition heals on its own without intervention. However, there are situations where symptomatic treatment can help.

The most important thing your doctor will do is reassure you. Your doctor will explain that pityriasis rosea is a harmless condition that will go away on its own. The rash will probably remain visible for a few more weeks and then slowly disappear.

If you have no itching or other symptoms, nothing else is often necessary. You can just go on with your normal life. You don't have to isolate yourself because the condition is not contagious. However, it is wise to avoid excessive heat because it can worsen itching.

If you do suffer from itching, there are various options. Lukewarm showers can help, but avoid water that is too hot. After showering, it's important to hydrate your skin properly with a neutral, odorless cream or lotion. Your doctor may prescribe an antipruritic medicine that you apply directly to the skin. For milder itching, over-the-counter products can provide relief. For more severe itching, your doctor may consider oral antihistamines.

In exceptional cases, when the rash lasts unusually long or the itching is very severe, UVB light therapy may be considered. This therapy is given by a dermatologist and requires multiple sessions. It is not a first choice but can be effective in persistent cases. Use mild soap, wear breathable clothing made from natural materials, and don't scratch the stains.

Because pityriasis rosea heals by itself and the exact cause is unknown, there are no treatments that can cure or significantly shorten the condition. It's important to have realistic expectations.

Antibiotics have no effect because it is not a bacterial infection. Even if the condition is caused by a virus, antibiotics won't help. The use is therefore unnecessary and undesirable due to side effects and resistance risks.

Antifungal medicines are also ineffective because it is not a fungal infection. While some fungal infections may have a similar appearance, pityriasis rosea does not respond to these treatments.

While good skin care is important, harsh scrubs or exfoliating treatments can make the condition worse. Scrubbing away the peeling does not help and can irritate the skin extra. It is better to treat the skin gently.

Extreme dietary changes or supplements have no proven effect on the course. There is no food or vitamin that can cure the condition more quickly. Avoid prolonged exposure to intense sun in an attempt to make the rash disappear. Uncontrolled sun exposure can damage your skin and increase the risk of pigment differences.

‍Is pityriasis rosea contagious?

No, definitely not contagious. You cannot pass it on to others, even through direct skin contact, sharing towels or clothing. While a viral infection may play a role, the rash itself is not transmissible. You can just have normal contact with family, friends and colleagues. Rare concurrent cases in households indicate a shared trigger, not infection.

How long does pityriasis rosea last?

The typical duration is six to eight weeks from the first mole. Some people heal more quickly, within four to five weeks, while others can take up to 12 weeks. In very rare cases, it may last longer. The rash reaches its peak after about two to three weeks and then gradually begins to improve.

Can I prevent pityriasis rosea?

Unfortunately, there is no known way to prevent it. Because the exact cause is not fully known and there are no clear risk factors that you can influence, prevention is not possible. It's not a matter of poor hygiene or wrong lifestyle choices.

Does pityriasis rosea come back after it has been cured?

It rarely comes back. For the vast majority, it is a one-off event. If you get a rash that looks like pityriasis rosea again, it's important to have your doctor evaluate it.

When should I see a doctor?

It's wise to see your doctor if you get a rash that looks like pityriasis rosea, especially to confirm the diagnosis and rule out other conditions. Medical advice is also good if the rash lasts longer than twelve weeks, the itching is very severe, or if you are concerned.

Does pityriasis rosea leave scars?

No, it does not leave permanent scars or skin changes. However, temporary differences in pigment may be visible. These may still be visible a few weeks to months after healing, but eventually disappear completely on their own. It's important not to scratch and protect your skin from excessive sun.

1. Skindr dermatologists
2. Health and Science: Pityriasis rosea
3. Ebpnet: Evidence-based guidelines for the general practitioner
4. Home doctor: Pityriasis rosea