Photodynamic Therapy (PDT) Instructions

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What is Photodynamic therapy?

Photodynamic therapy or PDT is a highly successful non-surgical treatment for pre or superficial skin cancers.  The treatment consists of applying a special photosensitising cream called Metvix (Methyl Aminolevulinate), to the affected area.  3 hours later the area is exposed to a red light source.  Both the cream and light combined will treat the abnormal skin cells.  Healthy skin is unharmed.  You will require treatment on 2 occasions two weeks apart.

What will happen to me when I attend for treatment?

Cream Application:

It is important you arrive promptly. If your lesion is very crusty please apply a moisturising cream daily to the area a week before treatment to help aid its removal, applying a plaster over the area will also help. As much of the crust as possible will be carefully removed on the day, otherwise the cream will not penetrate.

Metvix cream will be applied to the area(s) requiring treatment. The site is then covered with a dressing to keep out ordinary light.  Occasionally stinging can occur on the application of the cream.  It is important this dressing is not disturbed as the cream may become displaced from the treatment area.

You will then be given a time to return to the Clinic. This is normally 2¾ hours later.  You may leave the Clinic during this period.

Light Application:

When you return you will be asked to lie down so you are comfortable.

The excess cream and dressing are removed. Then the area is exposed to the special red light. During this time you may experience a hot, burning feeling .  You may have cold air blown over the area during treatment, to ease any discomfort, if you wish.

At the end of the treatment a dressing will be applied over the treated area.

What do I do when I return home?

You must keep the dressing on until the following evening (36-48 hours). This is to protect the area and prevent daylight getting to it.

Any pain experienced during the procedure normally stops as soon as the light source is removed, but some lesions can remain painful for 24 hours. You can take Paracetamol (up to 2 tables, 4 times a day).  An ice pack wrapped in a cloth can be applied for 10 minutes, at 30-minute intervals i.e. 10 minutes on and 30 minutes off.

The lesion may blister and ooze for a few days after treatment and the surrounding skin may become red.

If the treated area becomes very sore, red or crusty, it may mean it may have become infected and you may need antibiotics. Please contact the Clinic on 01865 320790.

How should I look after the area following PDT?

The area should be kept clean and dry. You may bathe or shower as normal, but avoid using soap on the area (plain water only) until the area has stopped oozing. Ensure the area is dried carefully and thoroughly, by patting gently with a clean towel.

Apply a moisturising cream e.g. Diprobase to the area daily

There is no need to apply dressings unless the skin lesion oozes.

When will I be reviewed?

You will usually have appointments to be seen again at the Clinic after 3, 6 and 12 months. The Nurses will arrange to see you again as necessary.


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