Psoriasis – Light Therapy Treatment Options


Clearly this is an extremely common skin condition, because over 3 million new cases of Psoriasis reported in the US reported each year.

It is non-contagious chronic autoimmune disease that mainly affecting the skin. Psoriasis actually changes the life cycle of skin cells. The skin effectively starts to produce cells faster than the body can shed them, so they start to build up rapidly on the surface of the skin.

This build up of extra skin cells form thick, scaly patches (psoriatic plaques). Typically, with plaque psoriasis they are commonly found on the elbows, scalp, knees and lower back of the patient.

There are six main varieties of Psoriasis. By far the most common form called Plaque Psoriasis, counts for about 80% to 90% of the cases reported and treated.


The triggers and causes of Psoriasis are not yet clear.  Many studies though have shown it to be linked to the immune system.

Another hypothesis is that the fault lies in the epidermis (the upper or outer layer of skin) and its keratinocytes. Keratinocytes make up 95% of the cells of the epidermis. The skin cells on the outer surface of the epidermis die but do not shed and form a tough protective layer. The cells below carry on  dividing to replenish the supply.

In normal skin the skin cycle is 28 days, for the cells to be created and then to die. I Psoriasis sufferers this cycle is reduced to just 2 to 6 days . This causes the dead skin cells to accumulate on the surface of the skin, in the thick scaly patches symptomatic of psoriasis.


In it’s most common form Plaque Psoriasis. The symptoms will include:

  • Red spots and patches. The patches enlarge and become scaly.
  • The upper scales will cascade in large quantities, while the lower layer of scaling remains fixed.
  • If the scales are scraped off, numerous small, bleeding foci can be seen underneath.
  • The skin plaques may become very itchy and painful. In severe cases, the plaques will grow and merge covering large area of skin.


Because Psoriasis is a condition which seems to runs families, it is thought that it could be genetic. But it is by no means certain that the person carrying the gene will ever develop Psoriasis. There does however appear to be certain trigger points.

Exposure to certain medicines, excessive alcohol intake, streptococcal infection in the throat and local irritation or damage to the skin can all contribute to a psoriasis flare up.. Stress can also be a for trigger psoriasis.


There are a wide variety of topical treatments like corticosteroid creams and ointments that can help keep Psoriasis under control. Various scalp treatments are also available in the form of foams, lotions and medicated shampoos. As with all chronic diseases it is long lasting and often difficult to treat.

A specialist dermatologist treating patients with severe psoriasis that is not responding topical to treatments may prescribe light therapy or stronger oral medicines.


Both UVA and UVB are component wavelengths in sunlight, UVB works better than UVA for psoriasis. The UVB from sunlight works in exactly the same way as UVB omitted by phototherapy devices.
Extreme caution is recommend for psoriasis sufferers when treating the condition with natural sunlight. Start with just 10 minutes at the same time every day.  Gradually increase exposure time by a minute every couple of days. Check carefully if the skin is tolerating it.
When sunbathing try to give all affected areas equal exposure to the sun if possible. Remember to apply high factor sunscreen on areas of your skin unaffected by psoriasis.

Careful with some topical medications as they can increase the risk of sunburn.

Patient being treated with PUVA or other forms of light therapy should limit or avoid exposure to natural sunlight. Best advice as usual check with your doctor.


Light therapy treatment can use either artificial or natural sources.

Sunlight Careful exposure of the skin to very limited amounts of direct sunlight can assist in alleviating symptoms. However, very close monitoring of exposure time and intensity is required because too much sunlight may cause skin damage and actually worsen symptoms.

UV (ultraviolet) light   An invisible light wavelength that is too short for our eyes to see. When skin is exposed to UV rays the activated T cells die off, resulting in a more normal skin cell replacement protocol. As well as less scaling and inflammation.

Patients should use sunlight treatment only under the supervision and advice of a medical professional.

UVB (ultraviolet B) – Normally given in a clinic, under the supervision of a dermatologist. This type of therapy can retard the production of skin cells. It is effective for the treatment of plaque psoriasis when the patient has not responded well to topical treatments.

We have written a very detailed article about the mechanism of red light therapy here.


psoriasis TreatUltraviolet B (UVB) is a natural component of sunlight and an effective treatment for psoriasis. UVB penetrates the epidermis and slows down the growth of affected skin cells. UVB treatment exposes the skin to an UVB light source for a calculated length of time on a regular schedule. This treatment can be administered in a medical clinic or at home.

Broad band and narrow band. UVB treatment are available. Narrow band UVB light bulbs just release a smaller range of ultraviolet light than broad band. Numerous studies have found that narrow-band UVB clears psoriasis faster, and produces longer remission times than broad-band UVB. It also is found to be effective with less treatments per week than broad-band UVB,

It has been noted by doctors that during initial UVB treatments psoriasis symptoms may worsen temporarily before improving. Typically the skin may redden and the itching may worsen from exposure to the UVB light. The amount of UVB exposure then may need to be reduced to avoid further irritation. These reactions tend to resolve themselves with continued treatment.


It is not uncommon to combine UVB with topical treatments to increase the effect  Combining UVB with systemic therapies may allow lower doses of medication to be used. Examples include lightt therapy combined with:

Coal tar therapy:  Coal tar helps to make the skin more receptive to the phototherapy.

The Ingram regimen: Is a combination of UVB therapy coal tar baths and anthralin-salicylic paste that remains on the patient’s skin for several hours or preferably overnight.


Like all light therapies UVB therapy requires a consistent and planned treatment schedule. Because of this patients who are treated initially at a medical clinic, often find it far more convenient to then begin using a light unit at home.

Home treatment is both an economical and convenient choice.

Home UVB is a medical treatment that still requires monitoring by a health care professional. It is critical to follow a doctor’s instructions and continue with regular check-ups.

311 nm UVB phototherapy—an effective treatment 

See Red Light Therapy Explained >>