Skin Glossary · Tests and Treatment

Phototherapy

Name: Meaning of Phototherapy
Published: 2026-08-25

Related terms · UV therapy

Phototherapy is a treatment that systematically uses medical-grade UV light for certain skin conditions such as psoriasis and atopic dermatitis. It is different from getting a lot of sunlight or tanning.

Reviewed by Korean Medicine Doctor Choi Yeon-seung · Last updated 2026-08-25

What is phototherapy?

It is a treatment where medical-grade ultraviolet (UV) rays are applied to the skin in prescribed doses. Phototherapy is a planned use of medical UV rays for certain skin conditions, such as psoriasis and atopic dermatitis. It is different from spending a lot of time in the sun or tanning.

How is it different from similar conditions?

It is a medical procedure that manages the treatment device and dosage, distinguishing it from self-tanning.

Why is this important in skin care?

A dermatology clinic may review this based on the extent of the condition and the response to previous treatments.

What should be checked based on my symptoms?

If you are currently undergoing this treatment, please inform your Korean medicine provider of the frequency and your response, and do not arbitrarily add further skin irritation.

Related conditions and medical guidance

Check guides where this term is used

Condition GuidancePsoriasisCommon symptoms of psoriasis include thick, raised inflammatory plaques and silvery-white scales on the scalp, elbows, knees, torso, palms, and soles. The skin may feel itchy, burning, stinging, or tight, and may crack dryly and bleed. Depending on the type, it may appear as small droplet-shaped skin changes, smooth rashes in skin folds, pustular skin changes on the hands and feet, or severe redness and scaling across the entire body. This may be accompanied by small pits, thickening, or crumbling of the fingernails and toenails, as well as joint pain, swelling, morning stiffness, and heel pain. If the entire body suddenly turns red, or if pustular skin changes occur with fever and a worsening general condition, seek prompt medical evaluation.Condition GuidanceAtopic DermatitisAtopic dermatitis is not confirmed by a single blood test or allergy test. In dermatology, the process centers on observing the appearance and distribution of dryness, itching, and rashes, as well as inquiring about the onset, the course of improvement and worsening, sleep disturbance, response to previous treatments, and exposure to irritants such as soap, detergents, scented products, and smoke. Medical history of atopic dermatitis, asthma, or hay fever for yourself and your family is also reviewed. In many cases, a physical skin examination and medical history are sufficient; blood tests or skin biopsies are selected when other causes of rashes must be ruled out. Symptoms, distribution, and progression are interpreted together rather than relying on a single test result.Medical Evaluation GuideWhat does Korean medicine look for when skin conditions recur after dermatological treatment?Please list separately what has improved and what still remains after dermatological treatment. If redness, oozing, or wheals have decreased or infection is controlled, record which treatment led to the improvement. If dryness, cracking, itching in the same area, or waking up at night remains, specific goals for Korean medicine treatment can be set. If there is new pain, pus, or rapid spreading, do not consider this part of the remaining recovery; seek medical evaluation first and do not change your prescriptions arbitrarily.

Evidence and Update Information

The definitions and safety standards in the materials below were referenced.

NIAMS Psoriasis GuideThe chronic course of psoriasis, scaly plaques, and accompanying symptoms have been confirmed.

What is phototherapy?

How is it different from similar conditions?

Why is this important in skin care?

What should be checked based on my symptoms?

Check guides where this term is used

Terms to know for easier distinction