State-of-the-art, personalized skin care
from experienced professionals
“A regular skin checkup can literally save your life.” Jennifer Krasnoff, MD

If you are dealing with eczema and psoriasis, a few rays may be good for you

We dermatologists are famous for telling you to stay away from the sun’s rays; and while that advice still stands, we make a (careful) exception for those with eczema and psoriasis. 

Months of moisture-zapping winter chill are a double whammy for those suffering from eczema and psoriasis – conditions marked by dry, cracked, irritated skin.   A variety of ultraviolet light therapies can provide safe and effective relief. 

Psoriasis and eczema (also known as ‘atopic dermatitis’) are conditions that occur when the body’s immune system goes into overdrive, causing skin cells to grow too rapidly. This abundance of new cells results in swelling, redness and flaky, dry and irritated skin.

What is Ultraviolet Light and how can it help?
Ultraviolet (UV) light refers to invisible light rays naturally given off by the sun.  Yes – these are the rays we warn you about – when they penetrate the skin they can give you a dangerous and painful sunburn as well as wrinkles and aging skin.  But under carefully controlled circumstances UVB and UVA rays actually can help calm and heal the skin. 

UV rays are grouped into different wavelengths including: UVA, UVB and UVCUVA rays penetrate the skin and cause it to darken or tan; UVB rays are most often responsible for sunburn. (UVC rays are absorbed by the earth’s ozone layer and don’t reach us at all.)

UV radiation can be administered in different wavelengths or ‘bands,’ with a single ‘narrowband’ (311-312 nm) treatment considered the most beneficial.   Compared with broadband (290-320 nm) treatment, which uses numerous rays, narrowband enables shorter exposure time, a shorter treatment course and longer periods of remission.

During light therapy, your skin is exposed to wavelengths of ultraviolet light using an artificial light source. A physician or nurse monitors your exposure intensity and time.

When UV rays penetrate the skin, they inflict a bit of damage to the skin’s DNA, resulting in the inflammation, swelling and pain we call a sunburn. This same process, when controlled, can serve to slow the growth of the excess skin cells, put the brakes on an overactive immune response and enable the skin to calm down and regenerate at a more modest pace.

So, UV Therapy is ‘intentional UV radiation,’  administered in measured doses by a physician,  in order to bring about gradual immune benefits.

A variety of light treatments are available depending on your needs.  Most frequently, targeted treatments are used on specific areas of the body.  We will sometimes recommend whole body treatment as well.

With any light therapy, the key to success with is consistency – treatments are usually repeated a few times a week, for as long as needed until the skin clears.

What you can expect from light therapy
UVB Phototherapy
UVBtherapy is thought to be the most effective treatment for psoriasis and recommended for many patients, including children.  During treatment, clothing is removed so that affected areas of the skin can be exposed to the light.  While broadband UVB was originally the preferred treatment, narrowband UVB (NBUVB) has since proven to be most effective.

For localized patches of psoriasis or eczema, we may use a device called a device called anexcimerlaser that emits a high-intensity beam of UVB light and targets localized areas of the body, such as the face, hands or feet. Administered twice weekly, excimer laser is frequently used to treat moderately resistant plaques. Treatments can last a few seconds to a few minutes.

Total body narrowband UVB (NBUVB) and Hand/Foot NBUVB
Full body, narrowbandUVB therapy may be used to treat more extensive plaques (red, scaly patches).  This process requires that the patient stands in a treatment light box (like an upright sunbed) that is fitted with NBUVB lamps.   

The hand/foot unit allows localized treatments to the hands and feet, sparing the rest of the body from unnecessary rays.

Treatment time and frequency will depend on your skin type and the nature of your condition.  Usually treatment can be seconds to minutes depending on if you are at the beginning or peak of your treatment course.  Treatment is administered three times a week for as long as needed, with exposure time often increasing with each treatment.

PUVA (Psoralen + UVA)
Like UVB, the sun’s UVA rays can slow the excessive cell growth of psoriasis and clear symptoms. UVA rays used in conjunction with a light sensitizing medication called Psoralen (a treatment called PUVA) can successfully ease symptoms for up to a year.   PUVA is recommended to adults with moderate to severe psoriasis, and not normally advised for children or teenagers. 

During PUVA, Psoralen is either taken orally or applied to the skin.  After a specified amount of time, exposed areas of the skin are treated with UVA rays.  As with UVB treatment, skin is exposed for a gradually increased period of time, and treatments continue a few times a week until the skin is cleared. 

Because these treatments do deliver ultraviolet light (a known carcinogen) to the skin, we carefully check for any sign of skin cancer, especially in the case of long term, high does therapy.  Short term, intermittent therapy is a very safe and effective way to keep symptoms at bay.

Natural Sunlight
If you can’t get to a dermatology office, a careful dose of natural sunlight can be effective too.  We recommend 15-20 minutes per day in the summer months.  During winter, UVB in the office is a safer option, as it ensures exposure to just UVB rays without the added harmful effects of UVA, infrared and other damaging rays.

Learn more about these conditions and light therapy treatment available in our office:

Download the PDF here.





Petaluma Office
165 Lynch Creek Way
Petaluma, CA 94954
 M-F, 8:00am-5:00pm
(707) 762-5531
Fax: (707) 762-5976



Hercules Office
500 Alfred Nobel Dr., Ste. 245
Hercules, CA 94547
M-F, 8:00am-5:00pm
Open Saturday for aesthetic services
 (510) 741-7418
Fax: (510) 741-7456


Billing office
Fax: 510- 741-7493

At Dermatology Associates of the Bay Area, our board-certified dermatologists serve patients at our Petaluma and Hercules offices. We are committed to the highest standards, and we offer a full range of cosmetic, medical, and surgical dermatology procedures, as well as quality skin care products.

Dermatology Associates of the Bay Area
165 Lynch Creek Way | Petaluma, California 94954 | Phone: (707) 762-5531 | Fax: (707) 762-5976
500 Alfred Nobel Drive, Suite 245 | Hercules, California 94547 | Phone: (510) 741-7418 | Fax: (510) 741-7456