Phototherapy

Question 1

Phototherapy

Answer 1

the use of ultaviolet light in the mgmt of severe dermatoses

Question 2

UVB

Answer 2

sunburn spectrum, higher energy but limited to the top layers of the skin

Question 3

UVA

Answer 3

deeper penetration but less energy

Question 4

Indications

Answer 4

AD, CTCL, LP, Morphea, PR, PSO, Vitiligo

Question 5

Contraindications to phototherapy

Answer 5

photosensitive disorders - actinic derm, dermatomyositis, use of photosensitizing meds, hx skin cancers, lupus, xeroderma, basal cell nevus syndrome, breast feeding

Question 6

phototherapy mechanism of action

Answer 6

reduce cutaneous t cell lymphocytes and mast cells, immune suppression

Question 7

PUVA (UVA with psoralens)

Answer 7

inhibits DNA replication and causes cell cycle arrest, suppresses infiltrating lymphocytes

Question 8

Dosing

Answer 8

determined by minimal erythema dose or by skin type. 2-3x a week usually, need eye protection, decrease tx as condition improves

Question 9

advantage of phototherapy

Answer 9

easy, well tolerate, home phototherapy option, spares healthy tissue from UV rad with target therapy, can induce remission

Question 10

disadvantages of phototherapy

Answer 10

time committment 2-3x week, photoaging, PUVA s/e of GI upset with oral pill, increase risk of skin cancer, PUVA ‘itch’