PUVA is a form of repigmentation therapy where a type of medication
called psoralen is given before exposure to ultraviolet light A (thus
the name PUVA). It is generally used for people with more extensive
Vitiligo (affecting greater than 20% of the body), and is the mainstay
of treatment for Vitiligo patients.

Psoralen makes the skin very sensitive to light. Combined with UVA, it
stimulates the production of the pigment melanin in the skin. Basically,
it serves to help the patient tan faster in a small amount of time. PUVA
therapy has a 50-70% chance of returning color on the face, trunk, and
upper arms and legs, whereas hands and feet respond poorly.


PUVA hand therapy

Psoralen can be taken by mouth or applied to the skin as a paint and can
even be added to bathwater, in which case the hands and/or feet are soaked
in the mixture for 30 minutes and then immediately exposed to UVA.

In most cases, at least a year of twice weekly treatments are required in
order to see good results.


A man receiving PUVA therapy

Types of PUVA:

Topical PUVA - A thin coat of psoralen is applied to depigmented
patches of Vitiligo 30 minutes before UVA light exposure. This
type of PUVA therapy is often used for people with a small number
of depigmented patches (affecting less than 20% of the body) and
can also be used for children as young as 2 years old.

Oral PUVA - A prescribed dose of psoralen is taken in pill-form
by mouth 2 hours before UVA light or sunlight exposure. This
type of PUVA therapy is often used for people with more extensive
Vitiligo (affecting greater than 20% of the body) and is not
recommended for children under the age of 10 because of the
increased risk of damage to the eyes, such as cataracts.


Instructions (from DermNet NZ):

Keep all scheduled appointments. Allow time for changing.
Tell the staff about your health problems, including 
medications and eye disease.
Do not apply any ointments or cosmetics except as directed
by your doctor or phototherapist.
Schedule treatments at the same time of day whenever possible.
Alcohol consumption should be minimal.
Avoid [additional] sun exposure on treatment and non-treatment
days.
Apply broad spectrum sunblock to face and hands before treatment.
Cover male genitalia--this area must not be exposed to UVA.
Wear the special goggles provided during treatment.
Wear wrap-around ultraviolet-protective sunglasses both indoors
and outdoors after treatment.
After dark, sunglasses must still be worn under fluorescent
lighting.
Wear fully-covering clothing outdoors and if near a window indoors.
Apply sunscreen to all uncovered skin after treatment.
Arrange to be seen regularly by your dermatologist.


PUVA treatment can cost approximately $6000 or more per patient for 1-1.5
years of treatment (120 treatments). This figure does not include travel
expenses to treatment centers nor the patient's loss of work time. What's
worse is that most insurance companies do not cover the costs of treatment,
as they believe Vitiligo is just a cosmetic problem. The patient is then
unable to get the proper treatment for this disease, which leads to the
patient being unable to obtain or keep a job (especially one that requires
interaction with the general public) due to their cosmetic disfigurement.

Side Effects:

Short-term

burning (sunburn) and redness
headache
nausea and vomiting
itching


Long-term

eye damage (if goggles are not worn during UVA treatment,
or if special UVA-blocking glasses are not worn 24 hours after
therapy)
premature skin damage and/or aging
nonmelanoma skin cancer
cataracts
discolored spots on skin

Some of the common topical psoralens that are combined with UVA light
are: methoxsalen (Oxsoralen®) and trioxsalen (Trisoralen®).

With PUVA (and most treatments for Vitiligo), complete repigmentation
cannot be guaranteed and relapse is possible.