Psoriasis is often seen as red elevated plaques with silvery scales at various sites of the body.
Most often you will see Psoriasis on the elbows, knees and scalp, but Psoriasis can appear anywhere on the body. Severity can vary greatly.
Psoriasis affects about 2 – 3% of the people in a country, and Psoriasis is equally common in men and women. It can start at any age, but most patients developPsoriasis in their twenties. There is a peak of Psoriasis during late teens or early twenties and a second peak during the fifties.
Duration of Psoriasis may vary a lot, but in most patients, the course of remissions and exacerbations goes on for many years or even an entire lifetime.
If treated the right way most people with Psoriasis will be living well with the condition
Classification according to type of lesion
Some dermatologists believe that the term "Psoriasis" in fact covers six or seven different conditions, which in the future may be distinguished from each other and treated separately. The effect of the drugs that are available today (e.g. local and systemic treatments) is to clear the psoriatic plaques and to prevent relapse.
Psoriasis is classified according to the type of lesion into the following subgroups
PlaquePsoriasis (which is the same as Psoriasis vulgaris)
Plaque Psoriasis (Psoriasis vulgaris)
Psoriasis vulgaris is the clinical term for plague Psoriasis. Vulgaris means “common” and Psoriasis vulgaris is the most prevalent form of Psoriasis affecting 95% of people with Psoriasis. Lesions are clearly demarcated and may be surrounded by a clear ring. The condition can appear on various parts of the body and lesions vary depending on the body part affected.
Plaques vary in size and number and they can be both thin and thick. Scratching results in the appearance of fine droplets of blood. The color of the plaques may vary in intensity, being redder towards the edge of a plaque than at the centre.
The plaques are often found symmetrically on the outer arms and legs, especially on both elbows and/or both knees, but any part of the body can be affected.
The plaques sometimes appear in certain shapes, and they are always clearly demarcated (it is easy to see where it starts and ends). It is sometime referred to as Psoriasiscircinata (from the Latin circum) where lesions are ring shaped.
Small, round, scattered lesions are typical of guttate Psoriasis or Psoriasis guttata. Instead of extensive, thick plaques, this type of Psoriasis presents with small red scaly dots which look like drops of water sprinkled over the body. Guttate Psoriasis is more prevalent in children and young adults than older adults and disease onset is strongly related to streptococcal throat infection (such as rhino-pharyngitis, pharyngitis or tonsillitis). This type of Psoriasis tends to go into spontaneous remission after several weeks and can reappear either in the same form, or as classical plaque Psoriasis.
Nummular Psoriasis is characterized by rounded plaques which are several centimeters in diameter. Their shape and size are more or less the same as a coin.
Skin care and Psoriasis: general points
What are the features of skin affected by Psoriasis?
When the skin is affected by Psoriasis, the epidermis renews itself too quickly. Cells are turned over in four to six days, instead of the usual three weeks. The skin becomes dry and dehydrated and so is less supple than is normal. It also becomes easily inflamed, resulting in the red color of the plaques that appear on various parts of the body, especially the arms and legs, trunk and scalp. Lesions are normally covered with fine white scale.
Psoriasis is a chronic disease which normally appears after the age of 15 and which waxes and wanes.
What can I do to soothe pain and itching?
If you are experiencing itchiness, you can try: Applying a moist tissue to the plaque and pushing down gently on it to rehydrate the skin.
Moistening the lesion with warm salt water and then applying Vaseline or pH neutral cream as recommended by a dermatologist or pharmacist.
Regularly airing your house or workplace as poor ventilation and an overly hot, dry or moist atmosphere can stop plaques from healing. Avoid rubbing or scratching plaques so as not to make inflammation worse. The skin should be treated extremely gently. You should also avoid disturbing the dead skin which builds up on the knees, elbows or scalp. Instead, it is best to allow scales to flake off naturally and gradually as the skin heals.
How should you wash skin affected by Psoriasis?
When you are washing, you should avoid rubbing and pulling the skin as much as possible. Opt for showers rather than baths which dry out the skin. You can take baths occasionally to help you relax as long as you do not spend too much time in the water and make sure the water is not too hot. Its maximum temperature should be 37-38°C.
You can use normal pH neutral soap. Scented products should be avoided.
After washing, do not pull dead skin off the elbows and knees.
Dry yourself thoroughly by patting the entire body with a towel.
Every nook and cranny should be dried. Particular attention should be paid to your ear holes and behind your ears, the armpits, the creases under the breasts, the umbilicus and the groin as well as the skin between your toes.
Can a person with Psoriasis go swimming?
People with Psoriasis can go swimming from time to time except during flares when the skin is more delicate. It is often good to remind other bathers that Psoriasis is not contagious so they are not at risk. Before entering the water, apply a little amount of Vaseline to your plaques in order to protect them from chlorine and other chemicals used to treat the water. Take a shower in warm, clear water when you get out. The skin should be dried by patting it with a soft towel.
What skin care products and cosmetics can someone with Psoriasis use?
People with Psoriasis should use basic and gentle soaps, deodorants, makeup and so on. Products for sensitive skin or babies are particularly suitable. People with allergies to certain perfumes should continue to use the same range of hypo-allergenic products as before their first flare. It should be remembered that some chemical ingredients and perfumes that trigger allergic reactions are sometimes used in air fresheners and fabric softeners.
If the skin in the armpits is inflamed, salt water should be used to wash it. Deodorants should not be used until redness has subsided. Products containing alcohol or perfumes are not recommended.
Normal makeup for the eyes, lips and face can be used, as can waterproof products. It is best to use cold wax to get rid of hair as this is less irritating than hot wax, depilatory creams or shaving, particularly if you have plaques on your legs or in your armpits.
Definition of Psoriasis
Psoriasis is a chronic inflammatory skin condition which affects approximately 1-3% of the world's population. It appears as red plaques covered with silvery scale that flakes away from the skin.
Psoriatic plaques are often found on the elbows, scalp and knees but can also affect other parts of the body such as the face, feet and mucous membranes.
Psoriasis is not contagious, nor is it caused by an allergy. However, the tendency to develop the condition can be genetically transmitted.
Psoriasis causes itching in 60% to 70% of cases
This type of Psoriasis affects less than 10% of patients. It can appear as a complication to plaque Psoriasis, as a result of taking certain medicines, or of abruptly withdrawing from them. Lesions are characterized by pustules. The palms of the hands, soles of the feet, fingers and nails are most affected.
Erythrodermic Psoriasis can affect most of the body's surface, and skin becomes erythemato-squamous (covered by red, scaling patches). Limited patches of pustules may appear.
Psoriatic arthritis is characterized by inflammation affecting joints and in some cases entheses (=the point at which a tendon inserts into the bone). It is estimated that approximately 1% of the world population is affected by psoriatic arthritis.
Most severe forms of Psoriasis
Some forms of Psoriasis are more severe and particularly resistant to treatment. These are pustular Psoriasis, erythrodermic Psoriasis and psoriatic arthritis. These should receive very careful medical treatment, in collaboration with dermatologists.
We talk about Psoriasis universalis when lesions are present over the entire skin. This form of Psoriasis is quite rare.
What skin care products should be used by people with Psoriasis?
When you have Psoriasis, it is hard to know which makeup remover or body lotion to use, especially in view of the ever-increasing number of products available. This section aims to provide you with information on face and body care products for sensitive skin.
Psoriasis is a chronic condition which tends to wax and wane. It is characterized by the overproduction of keratinocytes which leads to hyperkeratosis (thickening of the outermost horny layer of the skin) and by the appearance of red, inflamed patches of skin.
Although no complete skin care range has been formulated for psoriatic skin, it is important to use products that do not cause any irritation and which are preferably hypoallergenic. Products that irritate the skin may result in the Koebner phenomenon, where psoriatic plaques appear on irritated skin.
On the other hand, some products have a highly keratolytic effect and help to remove scale, which in turn allows topical medications (such as corticosteroids and vitamin D derivatives) to be better absorbed.
Lastly, emollients (moisturizers) should also be used as they improve the skin's suppleness and make it less rough and dry. Skin care products based on soft thermal spa water (which has softening and anti-inflammatory properties) are also particularly suitable for psoriatic skin.
Although skin care products cannot replace local treatments for Psoriasis, they can have a complementary effect.
They lead to a feeling of well-being by reducing discomfort and improving the appearance of the skin. When the skin is well moisturized, it looks better and feels softer, which improves self-esteem.
Skin care products can help improve the quality of life of people with Psoriasis.
Moisturizing body lotions
Psoriasis makes the skin dry and rough and damages the outermost horny layer of the skin, which becomes very thick. Cellular processes are disturbed and the skin has difficulty retaining water, which leads to dehydration. You should therefore use emollients, which make the skin suppler. They supply the horny layer with substances (such as urea, amino acids and lactic acid) which absorb and retain water, while reconstructing the skin barrier with anti-dehydrating agents (such as Vaseline, beeswax, vegetable oils and ceramides).
It is better to choose O/W (oil in water) products which are less greasy than those labeled W/O (water in oil). Products recommended for very dry and atopic skin (such as eczematous skin) are generally suitable for psoriatic skin.
However, psoriatic skin is sometimes inflamed, which is not necessarily the case for very dry skin. Atopic dermatitis is an abnormal reaction of the skin which manifests as a type of eczema known as atopic eczema. Although atopic dermatitis has features in common with certain forms of Psoriasis (redness and itchiness in particular), it does not cause the horny layer to become thicker.
No therapies have been specially formulated for particular types of Psoriasis or for specific phases (progressive or stable) of the condition. However, after a bath or shower, people with Psoriasis should use moisturizing treatments which are well tolerated and have long lasting effects. It is thought that this can halve the rate of skin renewal and very possibly slows the appearance of new flares.
It is important not to use an emollient just before UVA or UVB treatment as it can prevent the rays penetrating the skin. However, an emollient may be used on the previous day or evening.
Some products for atopic skin (enriched with Omega 3 and essential fatty acids) are also suitable for psoriatic skin, and especially for skin with itchy lesions. Although a lack of fatty acids has been shown to be typical mainly of atopic dermatitis, we can reasonably deduce that psoriatic skin also has an increased need for them because of its abnormally quick rate of renewal.
Keratolytic treatments for the body
Keratinisation is the normal process whereby the skin is renewed by keratinocytes, the principal cells in the epidermis. These cells, which produce keratin, function abnormally in Psoriasis and the outermost horny layer of the skin becomes thick and flaky. Because the keratinocytes are not eliminated in a normal fashion, the skin looks rough. Certain substances, such as salicylic acid, urea and lactic acid, can be used to combat hyperkeratosis (the medical name for thickened skin).
Salicylic acid is an active ingredient with keratolytic and antiseptic properties which is present in many products for irritated and scaling skin. Urea is both keratolytic and moisturizing. Alpha-hydroxy acids or fruit acids (such as glycolic acid and citric acid) have long been used in skin care for their exfoliant and smoothing effects as they help get rid of excess dead cells. AHAs with a lower (more acidic) pH have a greater exfoliant effect.
People with Psoriasis should seek to use AHAs which are as mild as possible, such as ammonium lactate. Kerato-regulators are available in creams and emulsions and help to get rid of built-up layers of skin and remove scale. They are particularly suitable for use on areas of the body and scalp where the skin has become very thick and scaly.
Most keratolytic products also contain active ingredients which help moisturize the horny layer. They can be used as a maintenance therapy in order to keep the skin moisturized and prevent relapses. During eruptions, these products can also help to soothe the epidermis and make the skin suppler.
Treatments for weeping skin
Psoriatic skin may sometimes weep, with lesions resembling small blisters appearing on the surface of the skin. These are filled with clear liquid that may be clear or yellow-tinged. When they break, either spontaneously or as a result of scratching, they appear to weep and sometimes look crusty. If they are on an area of skin subject to friction, they tend to reappear after they have been burst. The weeping can be caused by trauma or inflammation.
If you do not have lesions on your face, you can cleanse your face as you wish in line with your skin type, using soap, water, makeup remover, cleansing milk or gel. If you have acne, it is best to opt for gentle cleansing gels. If your skin tends to be dry, we recommend soap-free cleanser, toilet soaps and cleansing milks.
If you have psoriatic lesions on your face, it is important to keep your skin absolutely clean (by cleansing it in the morning and evening) and to apply a moisturizing cream daily, or several times a day if your skin is very dry. Although there is no absolutely ideal skin care product for Psoriasis, it is important to use products which do not irritate the skin. You can also steam your face with mineral water, which will help get rid of scale and soothe redness.
Dry your skin by patting it gently with a towel. During an eruption, you should avoid having facials at beauty parlors or applying masks and scrubs at home because of the risk of irritation.
However, when you are not suffering from an eruption, you may use products that are packed with as many active ingredients as you like (such as anti-ageing products), as long as they are well tolerated by the skin. However, products containing vitamin A derivatives should be used with care.
In Psoriasis of the scalp, the skin can become very thick and red plaques appear which are generally very scaly.
Keratolytic shampoos should be used as an aggressive therapy to detach scales and soothe itching. Keratolytic shampoos do not contain coal tar. You should apply the shampoo to the roots of the hair and leave it for five minutes. You should then rinse it out, and wash your hair again using a shampoo suitable for your hair type. As soon as scalp lesions have disappeared, you should use a gentle shampoo to avoid flaking. You can wash your hair every day as long as you use a suitable shampoo.
Keratolytic creams are also available to help get rid of scaling. For best effects, apply the cream to the scalp, cover the head with a shower cap and leave the cream on for two hours. You can dye your hair, apart from during flares, but you should avoid washing your hair with very hot water and blow drying it with very hot air.
Although exposure to the sun can be good for psoriatic skin, you should protect yourself against the harmful effects of UVA and UVB rays. Some sunscreens have been specially formulated for atopic skin and for children.
What are the different types of Psoriasis?
Psoriasis may appear at any age, but there are two peak onset periods; during childhood/early adulthood (early onset Psoriasis) and after age 40 (late onset). There is strong evidence for a genetic predisposition to Psoriasis, in particular to childhood Psoriasis. It is estimated that 71% of patients with childhood Psoriasis have a positive family history.
There are multiple forms of Psoriasis and they are often distinguished based on the location and appearance of the lesions. The presence and distribution of psoriatic plaques is highly variable; some people suffer from a single plaque of Psoriasis on a specific part of their body, whereas others suffer from Psoriasis all over their bodies.
Psoriasis is accompanied by itching in 60% to 70% of cases.
There is to date no permanent cure for Psoriasis and eruptions often recur. However, most treatments are related to significant improvements in quality of life.
Topical treatments of Psoriasis
A topical medication is one used externally, applied directly to the skin. The treatment which is typically a cream or an ointment is applied locally on the affected site.
Topical treatments are first line treatments, meaning that these treatments are usually tried before systemic treatments can come into play.
The Finger Tip Unit (FTU) is the keystone in how to apply a topical treatment correctly. The FTU is a simple, individual measure telling you how much cream or ointment to apply to a Psoriasis lesion. A FTU is the amount of ointment or cream covering the distance from the tip of your index finger to the first joint as the preparation is squeezed out of the tube -see picture below. One FTU will be sufficient to cover a body area of 2 hands. Thus 2 FTU's will be sufficient to cover a body area of 4 hands.
Calcipotrioland betamethasone combination
A new treatment in the form of a combination of a vitamin D3 analogue and a corticosteroid is available.
Should be applied once daily and is proven to be fast acting and effective. Most patients will be cleared within 4 weeks treatment.
Side effects are few. In a long-term safety study it was concluded that the product is well tolerated. Side effects are the same as for calcipotriol, although skin irritation is significantly less.
Aimed for people with mild, moderate or severe Psoriasis vulgaris, where no more than 30% of the body surface area is affected.
Calcipotriol is a vitamin D3 analogue for Psoriasis vulgaris. The mode of action is not fully understood, but it is believed that calcipotriol works by slowing down the hyper proliferation of keratinocytes and immunologic changes in the psoriatic skin.
Should be applied twice daily and approx. 70% of patients will be clear or almost clear after 8 weeks treatment.
The most frequent side-effects are burning, itching and skin irritation, which occur in about 10-15% of patients.
This form of treatment is very old, but still found in shampoos for mild scalp Psoriasis as well as in intensive hospital regimens.
The exact mechanism of action is unknown, but coal tar makes skin more sensitive to light and can help slow down the rapid proliferation of keratinocytes. Tar also helps reduce the inflammation, itching and scaling of the skin.
Improvement is often seen in a few weeks, but it can take up to 2 months to achieve maximum benefits.
Coal tar contains more than 10.000 ingredients, of which only about 50% have been identified, and there can be a wide difference in the formulations available.
Corticosteroids (also called steroids)
Corticosteroids and steroids are often used for mild-to-moderate Psoriasis. Steroids are fast acting, but safety of long-term treatment has not been studied.
Over-the-counter steroids are (in most countries) too weak to be effective on Psoriasis.
Moisturizers, bath and shower oils
Moisturizers, bath and shower oils can moisture the skin and help the skin to heal as well as help to maintain the skin clear and free from Psoriasis.
They can be bought over the counter in many different formulations and brands.
Salicylic acid is often combined with other topical products to enhance its effect. It is found in shampoos, soaps, lotions and gels and is a keratolytic i.e. it is primarily effective for removing scales. Salicylic acid has little therapeutic effect on the psoriatic lesion itself.
It is available in much different strength. Stronger preparations can irritate the skin if left on too long.
Tazaroteneis a topical retinoid which is used to treat mild-to-moderate plaque Psoriasis. It is a prescription vitamin A derivative, whichworks by slowing down the hyper proliferation of keratinocytes.
Psoriasis which resists treatment
The forms of Psoriasis which are resistant to treatment affect around 10% of patients. These may be localized or spread over the body. They include Psoriasis which previously improved with treatment and subsequently became resistant without an obvious cause; Psoriasis which has not improved with local treatment; and Psoriasisthat reacts badly to phototherapy. In some cases, Psoriasis turns out to be resistant because the patient has not followed instructions regarding therapy due to the constraints this places on his or her lifestyle. It should be noted that in children, an infectious agent may cause forms of Psoriasis that are resistant to treatment, and especially those which tend to recur. The dermatologist should question the patient closely in order to identify the factors which led to the Psoriasis becoming resistant. In particular, this means listing previous therapies, ascertaining if exposure to the sun improves lesions or not, and checking if the patient has started taking any new drug for another condition. This information will allow the dermatologist to suggest another local or systemic treatment, taking into account any possible side effects.