Overview

Photodynamic therapy (PDT) is used to treat some skin conditions like:

• small cancers that are only in the top layer of your skin
• pre-cancerous growths or patches on your skin

PDT involves applying a light-sensitive cream to your skin and shining a bright light on it. The light alone is harmless, but when the cream and light are combined, it destroys any abnormal skin cells.

We usually recommend 2 sessions of PDT, 1 week apart. The number of sessions we recommend will depend on the type of skin condition you have.

Benefits of PDT

PDT is a non-invasive treatment. This means that we do not need to make any cuts to your skin. You usually heal quickly after having PDT and have very minimal scarring.

You can have PDT multiple times if needed. It does not prevent you from getting other treatments in future if you need them.

Risks of PDT

We’ll discuss the risks and side effects of PDT before your procedure. Talk to us if you have any questions or concerns.

Short-term side effects

For a short while after the procedure, you might get:

• pain
• swelling – your skin might become pink (this can be harder to see on black and brown skin) and puffy
• blisters or ulcers – your skin might ooze a little
• an infection

These side effects usually go away after a few days.

Long-term side effects

There’s a chance you might get side effects that last longer, such as:

• scarring
• a change in skin colour – your skin might get darker or lighter

Before the procedure

You do not need to do anything to prepare for PDT.

If the area we’re treating is on your scalp, bring a hat. A hat can help protect your scalp from light while it’s still sensitive during and after the procedure.

During the procedure

Applying the cream

The first stage of PDT is to apply a light-sensitive cream called Metvix^®. We’ll do this when you arrive in the morning.

We’ll remove any scale or crust from the area of your skin we’re treating. We’ll roughen the surface of your skin to help it absorb the cream. We’ll apply the Metvix cream and place a dressing over the area to protect it from ordinary light.

It takes 3 hours for your skin to absorb the cream. During this time, you can either stay in hospital or leave and come back at the time we give you.

Shining a light on your skin

After your skin has absorbed the cream, we’ll remove the dressing from your skin and wash off any excess cream.

We’ll give you special glasses to protect your eyes from the light. Then we’ll shine a bright red light directly onto the area of your skin that needs treatment. This will only affect the areas that have cream on them.

This will feel uncomfortable. If you need a short break during treatment, we can pause until you feel ready to carry on. We might also use a cooling device to help you feel more comfortable.

We keep the light on your skin for about 10 minutes. After the light treatment, we’ll put a dressing over your skin.

After the procedure

Keep the dressing on your skin for 24 hours. This protects the area from direct sunlight. After 24 hours, remove the dressing and wash in the shower. You do not need any more dressings.

After you wash or bathe, gently pat your skin dry. Do not rub it.

A crust might form on your skin where it was treated. This means that your skin is healing. Do not pick it. Leave the crust to come away naturally over the next few days.

It’s normal for your skin to feel sensitive or itchy for a few days after having PDT. Your skin might also swell, blister or ooze slightly. If you need help managing any pain, you can take painkillers like paracetamol.

It can take 1 to 2 weeks for your skin to heal completely.

Follow-up appointments

We’ll invite you back for a second PDT session 1 week after your first one. You might have more sessions depending on your skin condition.

Once you’ve completed all your treatment sessions, we’ll invite you to a follow-up appointment to check how your skin is healing.