Psoriasis Symptoms, Causes & Treatments
Psoriasis is a type of skin disorder which causes a person’s skin cells to grow at a faster rate than they can be shed.
Normally, skin cells have a turnover period of around 28 days. This means that roughly once a month a new set of skin cells are produced and then the old cells are shed from the body.
In people with psoriasis, however, they have a much more rapid turnover rate, around two to six days, which doesn’t leave enough time for the dead cells to be shed and replaced with new cells.
The ultimate effect of this is an accumulation of dead cells on the surface of the skin, and this is what’s responsible for producing the characteristics symptoms associated with psoriasis.
Psoriasis can be characterized by the appearance of rough, dry, crusty and/or red inflamed skin, which can cover large areas of the body or smaller localized patches.
Generally, psoriasis is most likely to occur on the elbows, knees, scalp, chest and back. Although, it can also appear on any region of the body, such as on the legs or the hands.
Outbreaks of psoriasis can feel itchy, uncomfortable and sore, and the condition itself is considered to be chronic. This means that a person can suffer from psoriasis for many years, usually, their entire life.
However, in most cases, symptoms will decrease in severity over time as a result of the natural slowing of skin cell turnover that occurs with age.
Psoriasis symptoms can somewhat resemble those of acne, in terms of the behavior of outbreaks. Some people, for example, have a very mild form of psoriasis that only causes them minor discomfort and which may be barely noticeable at times.
Whilst other people may have a very severe form of psoriasis that causes a lot of discomfort, with outbreaks spread across large regions of the body.
In both cases, a person may at times notice a transience, or change, to their symptoms just as can occur with acne. Some days their skin appears to be better or even normal, but at other times their skin suffers from a very bad outbreak and may even be sore to the touch.
Psoriasis differs from acne, however, in that it cannot be spread from one part of the body to another by touch. It is also not contagious, so if you touch someone’s skin that has psoriasis you won’t be at risk of catching it from them.
Types of Psoriasis
There are five main types of psoriasis that can produce slightly different symptoms as shown below:
If you want to successfully treat your symptoms, you stand the best chance of doing so by first identifying the type of psoriasis you have:
Plaque Psoriasis (psoriasis vulgaris)
Most people, around 80%, who have psoriasis, have what is known as plaque psoriasis.
It appears as reddish or pinkish patches that have a scaly covering, and normally occurs on thicker areas of skin such as that on the elbows or knees.
Flexural Psoriasis (inverse psoriasis)
This type of psoriasis is more common amongst elderly adults and usually develops along skin folds where the skin is thinner such as the breast crease, armpits, foreskin, behind the knee, along the inner buttocks and groin area.
In people who are overweight, however, and have extra skin folds, such as along the abdomen and waist, outbreaks may also appear in those regions.
Flexural psoriasis can often be red, sore and painful due to the skin rubbing against itself in the folded areas.
This is a relatively uncommon type of psoriasis. It appears as lots of small white pus-filled pustules on the skin that may eventually take on a yellowish or brownish color.
Outbreaks can occur on specific regions of the body such as on the palms of the hands, on the fingertips, on the soles of the feet or on the toes. It can however, be more widespread and cover larger regions of the body.
As this type of psoriasis can be extremely painful, and in some cases life threatening, it usually requires the assistance of a medical professional in order for it to be treated.
This is another very serious type of psoriasis that can develop after a person has an outbreak of plaque psoriasis. It can somewhat resemble sunburnt skin, where the skin appears very red and inflamed causing it to feel sore and painful to touch.
It is not uncommon for this type to be spread over large stretches of skin, although it can also be localized to smaller patches such as on the knuckles or the elbows.
Although this type of psoriasis is relatively rare, it can suddenly appear after a bacterial or viral infection of the throat or respiratory tract or after some kind of localized damage to the skin such as a cut, burn or insect bite.
It is most common in people who are under 30 years of age, and outbreaks take on a characteristic “teardrop” shape with spots appearing all over the body or just on specific regions such as the arms or legs.
The exact cause of psoriasis is not currently known, but it is believed that the rapid skin cell turnover which causes the symptoms of psoriasis occurs due to an autoimmune response.
Essentially, cells of the immune system, called T lymphocytes, attack healthy skin cells which then results in an overproduction of new skin cells to replace those which have been destroyed.
This rapid turnover causes a buildup of cells on the surface of the skin, which then accumulates and forms a plaque.
As to why the immune system begins to attack itself, we are less certain of. Although it does appear that this disorder has some kind of genetic inherited component to it.
So if one of your family members have suffered from psoriasis outbreaks in the past, then there is an increased likelihood of you also experiencing outbreaks some time in the future.
Some possible, although as yet unproven, causes of psoriasis are:
The introduction of genetically modified (GM) foods has introduced new allergens into our food supply which may result in the immune system attacking the body’s own cells.
Considering the fact that autoimmune disorders have increased dramatically in the past few decades, this may explain why some people are suffering from skin disorders such as psoriasis.
The chemicals which we are exposed to in cosmetic products can cause skin allergies in people sensitive to those chemicals.
As these same chemicals may also penetrate through the skin, and be absorbed into the body, it is possible that they somehow interfere with the proper functioning of the immune system.
Vegetable oils, such as sunflower oil, contain large amounts of the polyunsaturated omega-6 fatty acids.
Individuals suffering with psoriasis have been shown to have elevated blood levels of arachidonic acid, a type of fat that’s made from omega-6 and causes inflammation in the body.
As a result, consuming too much omega-6 may therefore serve to stimulate the immune system’s attack on cells of the body, thereby accelerating and worsening the symptoms of psoriasis.
However, increasing one’s consumption of omega-3 fatty acids, such as from 2-3 daily grams of fish oil, can help to suppress the immune system which should then also lessen the symptoms of psoriasis.
This effect has been observed in populations where there is a high intake of omega-3 in the diet, such as the Eskimo population amongst whom psoriasis is virtually unheard of.
Treatments for Psoriasis
Although there is no known cure for psoriasis, there are a variety of treatments that can be used to manage the symptoms that a person experiences as shown in the table below:
If psoriasis symptoms can be managed, this may in turn help to prevent future outbreaks from occurring, reduce the severity of outbreaks or control existing outbreaks from getting worse.
There are two main types of treatments for psoriasis; internal and external. Below we look at some of the most common forms of these treatments:
External, or topical psoriasis treatments, are applied to the surface of the skin and can come in a variety of forms such as:
Coal Tar Extract
Coal tar extract is often added to shampoos as an anti-dandruff treatment, although it can also be found in creams and lotions.
Coal tar acts as an anti-inflammatory, and so it can be useful when applied to skin that is red and inflamed. In addition, because coal tar helps to break down keratin, topical application can reduce the thickness of skin thus softening it and reducing scaling.
The use of coal tar extract however, has several disadvantages. The most obvious is that it can cause a lingering smell, which may cause a person to feel self-conscious especially if they do not like the smell that it leaves behind.
Coal tar application can also increase the sensitivity of the skin to the sun, which subsequently makes it more vulnerable to sun burns.
In addition, there are also concerns about the use of coal tar in cosmetics being linked to lung cancer, especially when it is used as a shampoo where the vapors that it produces can be breathed into the lungs when a person is showering.
Topical corticosteroids are generally only used on small localized outbreaks and not on outbreaks that cover large regions of the body. Some examples of topical steroids used for psoriasis are Alphosyl HC cream, Eumovate, Betnovate, Dovobet and Halciderm.
They work by suppressing the inflammatory response in the skin. But due to the fact that topical steroids only suppress the inflammatory response, they do not actually cure anything and the effects that they produce only last for as long as the treatment is being applied.
However, even though topical steroids can be very effective in treating the symptoms of psoriasis, they should only be used for a short period of time because prolonged use can make symptoms worse.
As a result, this treatment should only be used under doctor supervision so that your skin can be closely monitored to see how it is reacting, and the treatment stopped if your body is developing a resistance to it.
Vitamin A derivatives known as retinoids such as tazaroten, work by reducing skin cell turnover rate and by reducing inflammation.
Some retinoids, however, can accumulate in the body, and so this type of treatment is normally only used for a maximum of 12 weeks. Over-usage can result in skin irritation, burning and increased sensitivity to ultraviolet light.
Derivatives of vitamin D, such as calcipotriol, calcitriol and tacalcitol are usually applied topically to the skin in the form of a cream or lotion.
This type of treatment works by slowing down the turnover rate of skin cells, thereby helping to reduce the accumulation of dead cells which can form plaques.
Because vitamin D is a more natural form of treatment compared to topical corticosteroids, it is generally considered to be safer to use on a long-term basis.
However, it typically takes about 12 weeks before this treatment reaches it maximum effectiveness, so you will have to wait a few months before you start to see an improvement in your condition.
Light Therapy (phototherapy)
Because it can be undesirable to treat large areas of the body with topical medications, people who suffer from widespread psoriasis are sometimes recommended to undergo light therapy by their dermatologist or physician.
Treatment of the skin occurs with ultraviolet B (UVB) light, and has the effect of slowing down the rate at which the skin renews itself and suppressing the skin’s immune response whilst simultaneously acting as an anti-inflammatory. This therapy is given over a period of 10 weeks with treatment sessions occurring two or three times a week.
One major disadvantage of using light therapy to treat psoriasis however, is that long-term exposure, or too much exposure, to UVB can be harmful to the skin.
Excess exposure to UVB rays for example, can cause burns, premature aging and increase ones risk of developing skin cancer. As a result, these factors limit the long-term usage and effectiveness of light therapy.
Glycolic acid works by removing dead skin cell buildup and can therefore be useful as a maintenance treatment to keep your psoriasis under control.
This is a relatively safe treatment to use and glycolic acid can be found in many commercially available skin care products. It is most effective for minor cases of psoriasis.
An alternative that may be used in replacement of glycolic acid is salicylic acid, as this produces similar effects on the skin.
Aloe vera gel that is taken from the inner leaf of the aloe vera plant is a safe and effective natural treatment for reducing itching, burning or inflammation of the skin.
It provides immediate relief to inflamed skin, although its effects tend to be relatively short-lived so repeated applications are required in order to maintain its beneficial effects.
Chamomile applied topically to the skin can act as an anti-inflammatory which reduces swelling and has a calming effect on the skin.
Chamomile oil rather than chamomile tea is used for this purpose, as the tea will generally be too weak to produce any noticeable effects. In addition, being water based, a tea based preparation will not stay on the skin for very long like an oil would.
Moisturizers, or emollients, can be used as an anti-psoriasis treatment to moisturize the skin so that it doesn’t dry out and crack. This can help to prevent scaling and reduce itching.
A very effective moisturizer to use for dry skin is emu oil, which also has anti-inflammatory properties to soothe irritated or inflamed skin.
Internal treatments are medicines which come in the form of a capsule or tablet that is taken orally. Such treatments are usually only available from a hospital or with a doctor’s prescription as they can cause more severe side-effects than the external topically applied treatments.
Some of the most common oral medications that are given to treat psoriasis include:
This medication works by slowing down the rate at which skin cells divide and multiple, which can therefore help to reduce scaling and plaque formation.
Side effects of this psoriasis drug can include allergic reactions, mental confusion, nausea, stomach pains, skin irritation, vomiting, vision problems and hair loss amongst many others.
Due to these side effects, methotrexate is usually only prescribed when a person is unresponsive to other first line treatments.
Acitretin is a derivative of vitamin A that can be taken as an oral psoriasis medication. Its main mechanism of action is to regulate skin cell division.
Acitretin is only used for very severe forms of psoriasis as it stays in the body for a very long period of time where it bioaccumulates. Long term usage can result in very serious side effects such as damage to the liver and increased fluid pressure on the brain.
This psoriasis treatment should not be taken by pregnant women as it can harm the developing fetus.
Treatment with ciclosporin takes around one month before noticeable effects are seen. It works as an immunosuppressant by suppressing the activity of T lymphocytes in the dermal and epidermal layers of the skin.
Side effects can include increased hair growth on the face, nose and arms, increased cholesterol levels, blood in urine, mood disorders and heart rate abnormalities.
Hydroxycarbamide slows down the rate at which new skin cells are produced. It can result in side effects such as nausea, vomiting, hair loss, abnormal liver function and may increase ones risk of developing leukemia.
Biological Agents (Biologics)
Biologics such as Adalimumab, Etanercept, Infliximab and Ustekinumab are a relatively new type of treatment for psoriasis. They can be administered via a intravenous injection or injected directly into the skin.
Biologics work by targeting immune cells directly rather than the symptoms which overactive immune cells can cause.
Their main mechanism of action is to reduce the number of immune cells, block the activation of immune cells or stop immune cells from carrying out certain functions. This, however, may compromise one’s immune system as a whole thereby making a person more susceptible to disease and infection.
Out of all the treatments available for psoriasis, external treatments are considered to be “first line”. This means that they are used first, and if the symptoms of psoriasis do not clear up or improve, then the internal treatments are used as a last resort or “second line” treatment.