Dermatologists were among the first specialists to harness the power of phototherapy to ease skin conditions. Today, light therapies are growing not only to treat skin diseases, but to rejuvenate the skin and tackle skin problems such as acne. More than skin deep, phototherapy can make us healthier and treat a host of health conditions, from seasonal affective disorder (SAD) to more serious illnesses such as cancer and stroke. This article will shed light on new therapies using all the wavelengths — from UV rays to visible light ranges to infrared light — to improve both skin and health. 

Ultraviolet light

The ultraviolet (UV) range is light with a short wavelength from 10–400 nm and represents less than 10% of total solar radiation. UV light is mainly known for its harmful effects — too much can cause sunburn, skin cancer and DNA damage; but in the right dosage, UV rays have health benefits, such as producing Vitamin D — a key vitamin to keep us healthy and protected from serious diseases. On the skin, UV light therapies can help treat skin conditions. Although the rays cause damage in high doses, in small, moderated amounts, UV light is thought to reduce inflammation, helping stifle conditions such as eczema, acne, psoraisis and vitiligo.

Dr William B. Grant, who runs the Sunlight, Nutrition and Health Research Center in San Francisco, thinks that in the future, we might look at UV light differently. The health benefits of ultraviolet-B (UVB) irradiance and vitamin D are coming into sharper focus as more research results are published. There are now approximately 100 conditions and diseases linked to low serum 25-hydroxy vitamin D concentrations.

Visible light

Visible light is also being used to treat skin conditions. One such popular treatment is known as photodynamic therapy (PDT). PDT comprises the topical delivery of photosensitising drug 5-aminolevulinic acid (ALA), or methylaminolevulinate (MAL), followed by irradiation with light to destroy tumour cells. Over the past 25 years, PDT has been useful in the treatment of actinic keratoses and certain non-melanoma skin cancers, such as Bowen’s disease and basal cell carcinoma. It is a simple treatment; dermatologists apply the photosensitising agent topically, which needs to sit on the skin for 3 hours before a red or blue light is irradiated. Today, we are seeing a new generation of medical at-home light devices that enable the patient to return home rather than waiting 3 hours in a doctor’s office.

Ambulight PDT, developed by Ambicare Health (UK), is a single-use, on‑the-go light device with a peak wavelength of 640 nm, which is plastered directly to the skin lesion. The patient will keep it on for 3 hours with the light off and 3 hours with the light on. The manufacturer calls it ‘therapy in motion’.

[pull_quote align=”left” ]PDT is being researched to treat skin ageing (fine lines and wrinkles, hyperpigmentation, rosacea) as its most common side-effect is a local rejuvenation of the skin tissue that has been treated. [/pull_quote]Some northern European countries are also experimenting with daylight‑mediated PDT.  Daylight‑mediated PDT reduces the time a patient spends in a doctor’s office and may serve as an alternative to conventional PDT. In a randomised study carried out in 2011, the Department of Dermatology at the University of Copenhagen showed that daylight PDT can be an effective and convenient treatment as there is no need for a medical light source for patients with multiple thin actinic keratoses. The procedures were easily performed and 2 hours of daylight exposure resulted in uniformly high response rates when conducted in the period from June to October in Nordic countries. All 20 patients enrolled in the study were given sunscreen. Sun-activated medical and non-medical therapies could become a very dynamic segment in the next 5 years.

The medical PDT market is growing, and a new actor is entering to challenge the two leading brands, Levulan from Dusa and Metvix from Galderma. The German pharmaceutical company Biofrontera is completing phase 3 clinical trials for its new drug BF-200 ALA, with an ALA concentration of 10% (lower than the leading actors, but with similar results according to company’s tests).

PDT is also being more researched to treat skin ageing (fine lines and wrinkles, hyperpigmentation, rosacea) as PDT’s most common side-effect is a local rejuvenation of the skin tissue that has been treated. Some studies have shown that dermal thickness increases, along with improvements in collagen and elastic tissue.