UV Light Therapy and its Applications

Article published on Dec. 11, 2015
Article published on Dec. 11, 2015

This article has not been vetted by an editor at Paris HQ

​UV Light Therapy and its Applications

What is UV Light Therapy?

UV (Ultraviolet) Light therapy, which is also known as UV Light treatment, is used to treat a wide variety of skin conditions including eczema, psoriasis, vitiligo and even lymphoma of the skin in some cases. Essentially the therapy involves exposing the skin to either UVA or UVB, which are types of UV rays that we normally associate with sunlight. In fact, a large number of sufferers of eczema/psoriasis will notice a marked improvement in their condition if they are exposed to sunlight during the summer. UV Light Therapy safely administers this same exposure to UV under controlled, monitored medical conditions.


The two types of UV Light therapy take the form of either UVA or UVB. UVA is commonly referred to as PUVA due to the inclusion of psoralen (the “P” in PUVA).

UVB treatment actually comes in two forms - UVB broadband and narrowband. In the past broadband was widely used, but now narrowband is becoming the standard option for eczema and psoriasis due to the fact that it is more effective and therapeutically targeted, thus reducing the chances of the side effects discussed later in this article.

PUVA, also known as photochemotherapy is a combination treatment whereby psoralen is introduced to the body either orally or topically. Psoralen makes the skin more sensitive to UV light which aids in the UVA treatment of the skin. PUVA can be used to treat lymphomas affecting the skin and similarly to UVB, can also be used for eczema treatment.

UV Light Therapy Treatment Regime

Psoriasis, Eczema and dermatitis are typically treated using UVB (Narrowband) and involve between 2 and 3 treatments per week. Initially the exposure time is limited to around 5 minutes and this is gradually increased over the period of treatment. The maximum treatment time this will be raised to is 30 minutes but in the majority of cases an exposure time of this length is not required. Because patients tend to react differently to treatments, the actual amount of treatments required will differ from person to person.

PUVA treatments generally follow the same approach with between 2 and 3 treatments per week. Due to psoralen it is recommended to wear sunglasses and to protect your skin against the skin in between treatments.

UV Light Therapy Side Effects

As with most medical treatments, there is a potential for side effects to occur with UV Light Therapy. The short term effects can in some cases include redness of the skin, dryness and itching (which can both be managed by applying an emollient after treatment) and rashes.

Longer term, more serious side effects, which have a very small chance of occurring following frequent use of UV Light Therapy are skin cancer and ageing of the skin.

To minimize the chances of the longer term problems, the number of treatments is normally kept below a certain level over the lifetime of the patient. This is similar to the way that physicians recommend limiting your exposure to sunlight to reduce the chances of skin cancer.