Ultraviolet light treatment (phototherapy)

Ultraviolet (UV) light treatment uses part of the UV light range to treat:

• cutaneous T cell lymphoma (CTCL) – a type of cancer affecting the skin

• other skin conditions such as ​graft versus host disease (GVHD)​

You might also hear this treatment called ultraviolet light phototherapy.

Treatment lamps produce UV light rays to reduce ​inflammation​ on the skin. There are different types of UV light treatment:

• narrowband ultraviolet B (NB-UVB) treatment – this is the most common type

• psoralen ultraviolet light A (PUVA) treatment - this is less common

UV light treatment is a specialised treatment that you have at a phototherapy unit in a hospital.

In some rare cases you might have phototherapy at home.

This information is about having treatment as an ​outpatient​ in hospital.

Having NB-UVB treatment

You remove your jewellery, watch and clothes just from the area where you are having treatment.

You should wear the same clothes each treatment, so it covers the same area each time. This is because the dose of treatment increases at each session. So it might cause burning if a different area of skin is exposed.

Everyone wears goggles. This is to protect your eyes from the UV light. The hospital provides these.

You might wear a visor to protect your face if it isn’t in the treatment area. 

You must cover your ​genitals​ if you’re male, this may be with a black sock or jockstrap. Keep all the coverings in place during the light treatment.

You then stand in the cubicle with the door closed and the fluorescent tubes switched on.

You might feel quite warm. This is normal. You are inside the cubicle for up to 10 minutes, but usually for a much shorter time.

You still wear goggles if you’re just having treatment to a smaller area.

How often do you have NB-UVB treatment?

You have NB-UVB treatment 2 to 3 times a week. You have treatment for approximately 10 to 15 weeks depending on how well it’s working.

This is about 24 to 30 treatments.

After care and side effects of NB-UVB treatment

There are possible risks and side effects to all treatments including NB-UVB treatment.

Your doctor or nurse gives you instructions after your treatment. It's important to follow these to prevent serious side effects.

Skin after care

It's very important to protect yourself from the sun to reduce the risk of sunburn after treatment. Things that you should do include:

• Keep your skin and lips covered from sunlight or sun lamps. Wear sun protection factor (SPF) lip balm and sunscreen.

• Use a high SPF sunscreen of at least SPF 50 with a 4 or 5 star UVA protection. Apply this onto all areas of skin exposed to light. Reapply regularly and after you have been in contact with water.

Common side effects of NB-UVB treatment:

Skin rash

NB-UVB treatment can cause a skin rash. It is called a polymorphic light eruption. It looks like small red or dark bumps. But in some cases, you might have larger areas of red or dark changes, or small blisters. This is a more severe side effect that can happen from time to time.

Let your healthcare team know if you notice these skin changes. You might be able to have creams or medicines to help.

Skin colour changes

Depending on your skin tone, your skin might go pink, red or purple. Or you might notice that you have areas of skin that get darker.

Generally, this develops about 3 to 5 hours after NB-UVB treatment. It is usually at its worst between 12 and 24 hours after treatment. It usually gets better around 3 days after treatment. The timing can vary. It depends on your dose of NB-UVB.

Itching

You might have itchy skin after NB-UVB treatment. Let your team know if you are itchy.  Ask if you can have medicines such as creams or ​antihistamines​ to help relieve the itching.

Cold sores

If you are prone to getting cold sores, this treatment can increase your chance of getting them. Let your healthcare team know. They can give you advice on how to lower the risk of getting one during treatment.

Having PUVA treatment

You usually take psoralen as tablets. Less commonly, you might have psoralen as a liquid that you put into the bath and soak in.

Taking your tablets

You swallow your tablets with a small amount of food or milk as it can make you feel sick. You wait for 2 hours for your body to absorb the psoralen. 

Just before treatment:

You remove your jewellery, watch and your clothes from the treatment area.

You put on goggles to protect your eyes from the UV light. You might wear a visor to protect your face if it isn’t in the treatment area. 

You cover your genitals if you’re male, this may be with a black sock or jockstrap. Keep all coverings in place during the light treatment.  

During treatment:

You stand in a cubicle with the door closed and the fluorescent tubes switched on.

The light treats the sensitised skin cells. You might have some tingling or heat in your skin. This is normal and not harmful.

The dose and amount of time you need to spend in the cubicle depends on several factors including:

• your type of skin condition

• your skin tone

How often do you have PUVA treatment?

For CTCL you might have PUVA treatment 2 times a week for up to 30 treatments. 

You might need future treatments if your skin gets worse again. Some people might have a repeat course of treatment, usually after a year or so. 

You can't usually have more than 5 courses of PUVA over your lifetime. But sometimes, you might be able to have extra courses for your hands and feet.

Get more information on CTCL and its treatment

After care and side effects of PUVA treatment

As with all treatments, PUVA has some side effects. Psoralen is a photosensitiser. This means that it makes your skin and eyes very sensitive to light.

Your doctor or nurse gives you information to follow after your treatment. It's important to follow these to prevent serious side effects.

Eye after care

Eye protection is very important. The psoralen tablet makes you sensitive to the light. So eye damage can be caused by:

• sunlight

• daylight

• light through a window

You must wear eye protection until at least the end of daylight hours on the day of your psoralen. This means wearing sunglasses when exposed to the sun. You need to wear sunglasses outside even on cloudy days, until the end of daylight. If you are near a sunny window inside, you must also wear them.

Your nurse can test your glasses to make sure they have enough protection. If you don’t wear eye protection, you might have permanent eye damage.

Skin after care

Psoralen makes the skin more sensitive to light. You will burn more easily than usual in the sun, especially on the day you have treatment. It's very important to protect yourself from the sun.

• Don’t expose your skin or lips to sunlight or sun lamps for 24 hours after taking the psoralen. Wear SPF lip balm and sunscreen.

• Use a high SPF sunscreen of at least SPF 50 with a 4 or 5 star UVA protection. Apply this onto all areas of skin exposed to light. Reapply regularly and after you have been in contact with water.

• On treatment days make sure that all your skin is covered by wearing long sleeved clothing, gloves, and enclosed shoes. You also need a wide brimmed hat to protect your face, ears and head.

Common side effects of PUVA treatment:

Feeling sick

Psoralen may make you feel sick for a few hours after you take it. Try eating little and often. Tell your doctor or nurse if you feel sick. They can give you anti sickness medicine. 

Skin colour changes

Depending on your skin tone, your skin might go pink, red or purple. Or you might notice that you have areas of skin that get darker.

This skin change generally happens about 2 to 5 days after the day of treatment.

Itching

You may have itchy skin for a few days after PUVA treatment. Check with your team, but using non perfumed moisturisers after the treatment can help.

Skin rash

PUVA treatment can cause a skin rash. It is called a polymorphic light eruption. It is usually mild but can be severe. It looks like small red or dark bumps. But in more severe cases you might have larger areas of red or dark changes. Or you might have small blisters.

Let your healthcare team know if you see these skin changes. You might be able to have creams or medicines to help.