Sunlight, Lemonade and Langerhan’s Cells

Psoralens are natural products found in plants such as limes and lemons, celery, bergamot, parsley, figs, and cloves.

Psoralens are an old and effective natural treatment for skin conditions. In ancient times, doctors gave people with skin problems herbs that were most likely psoralens, and then told them to expose their skin to sunlight.

Types of Psoralens

Psoralens affect your DNA to stop cell growth in one of two ways. One group intercalates, or weaves itself into, DNA strands after your skin is exposed to ultraviolet light. This group includes 5-methoxypsoralen and 8-methoxypsoralen. The second group creates monoadducts, or links, to an individual base — the cross-pieces inside a DNA strand.

How Do Psoralens Work?

Psoralens boost the amount of ultraviolet light your skin absorbs. This lets the light into your skin. The ultraviolet radiation helps treat severe skin diseases like psoriasis, vitiligo, polymorphic light eruption, and cutaneous T-cell lymphoma, a type of cancer.

Ultraviolet light can slow down the overgrowth of skin cells that form psoriasis plaques, or rashes. In the 1970s, doctors found that psoralens and ultraviolet light together could clear up psoriasis skin plaques. It can also help treat vitiligo, which is a loss of pigment in the skin.

PUVA is about as effective as biologic drugs for psoriasis in 80% of people with this skin disease.

What Happens During PUVA?

You take psoralen capsules about an hour before a whole-body PUVA treatment.

After you remove the clothing over the treatment area, you step inside a cabinet fitted with UV bulbs. Treatments will start off short, about 1 to 10 minutes, and increase in length each time.

Possible Side Effects

Psoralens can make your skin more sensitive to sunlight. They can raise your risk of sunburncataracts, and skin cancer. And your skin might age faster.

Don’t use psoralens as a way to get a quick suntan. You should use these only as directed by your doctor.

Other short-term side effects of oral psoralens include:

And then there is the other side of the coin…8)

Citrus Consumption and Risk of Cutaneous Malignant Melanoma

Citrus products are widely consumed foods that are rich in psoralens and furocoumarins, a group of naturally occurring chemicals with potential photocarcinogenic properties. Citrus consumption was associated with an increased risk of malignant melanoma in two cohorts of women and men.

However, whether dietary consumption of psoralen-rich foods may increase melanoma risk is unknown, and whether the public should be advised about dietary psoralens remains a question.

Don’t eat limes, carrots, celery, figs, parsley, or parsnips while you take oral psoralens. It could boost the amount of natural psoralen in your system and make your skin even more sensitive to the sun.