WHAT IS PUVA PHOTOTHERAPY?
PUVA (P + UVA) is an abbreviation, with the P standing for psoralen and UVA for ultraviolet light type A. The
principle of PUVA therapy is that you take a tablet or capsule containing psoralens (also called 8-MOP capsules) just before the treatment, usually an hour beforehand. These psoralens make the skin extra sensitive to UVA light, making the therapy more effective.
UVA light is part of natural sunlight. The sun emits all kinds of light and heat, including white light (visible light, daylight), heat (infrared rays), UVA light, which gives you a tan, and UVB light, which can cause sunburn if you stay in the sun for too long without using sunscreen.
Sunlight, especially the UVB and UVA components, appears to have a healing effect on numerous skin diseases. Therefore, most hospitals have various types of light booths in their dermatology departments. The most common are light booths that emit narrow-spectrum UVB . These booths contain UVB lamps that primarily emit the healing component of UVB, while the component that can cause sunburn is filtered out. These are very different from those used in tanning salons for tanning, which primarily contain UVA lamps. UVA light is also used to treat skin diseases, but this only works if the lamps produce a very high amount of UVA ( high-dose UVA-1 booths) or if UVA light therapy is combined with medication (psoralens) that makes the skin extra sensitive to UVA light. This combination of Psoralen pills and UVA is called PUVA therapy.
HOW IS PUVA LIGHT THERAPY GIVEN?During PUVA therapy, you will be in a light booth. To make your skin more sensitive to UVA light, you must take the prescribed number of psoralen tablets (8-MOP capsules) one hour before the light treatment. These capsules remain effective for 8 hours. After taking the capsules, it is advisable to protect your eyes with UVA-blocking sunglasses. UVA light is also a component of sunlight, fluorescent light, and television radiation. Continue to wear the sunglasses until the capsules have worn off, so for up to 7 hours after the treatment.
A light treatment schedule will be determined based on your skin type (light or dark, blond or brunette, easily sunburned or not). Initially, you will be in the booth for a very short time. At each subsequent visit, the light treatment time will be gradually increased to prevent sunburn. The skin will be exposed to the light 2-3 times a week. The duration of the PUVA treatment varies from person to person but can last 2-3 months. To protect your eyes, goggles must be worn during the light treatment.
Light therapy with UVA light
Nowadays, it's also possible to receive light therapy at home. Your dermatologist will then contract a company that will deliver a unit to your home and explain how it works. The units aren't as large or powerful as those used in hospitals, meaning you'll need to spend more time in them. It's only possible if you have the space, are proficient in operating the device, and your health insurance covers it for your skin condition. Standard psoriasis and atopic eczema are usually covered, but sometimes not for other skin conditions. The advantages of home therapy are the absence of travel, privacy, and flexibility. The disadvantages are a longer exposure time, the risk of sunburn if not performed correctly, and the lack of supervision and guidance. If you have light therapy performed in the hospital, you can always consult a dermatologist to adjust the treatment if it doesn't work.FOR WHICH SKIN CONDITIONS CAN PUVA LIGHT THERAPY BE USED?PUVA light therapy is used for the following skin diseases:
- psoriasis
- eczema
- pityriasis lichenoides
- cutaneous T-cell lymphoma and lymphocytic infiltration of the skin
- vitiligo
- light allergy (habituation)
- and other rare skin diseases such as:
- necrobiosis lipoidica
- scleroderma (high dose UVA1)
- acrodermatitis continua and pustulosis palmoplantaris
- granuloma annulare disseminata
- parapsoriasis
- Sneddon Wilkinson diseaseWHAT ARE THE SIDE EFFECTS?The UVA treatment will give you a tan. Most people don't find this a problem, and sometimes they even enjoy it. But that's not the case for everyone. Even if you have pigmented skin, you should be aware that it will darken considerably with the PUVA therapy.
The standard tablets can cause nausea. These tablets are particularly taxing on the liver, which is the organ responsible for breaking down these medications. Not everyone tolerates the pills well. If necessary, the number of tablets can be reduced, or an additional anti-nausea tablet can be given.
There is a risk of sunburn during light therapy. The intensity of the light unit should be adjusted to your skin type, but things can still go wrong, resulting in redness and peeling skin (sunburn). This can happen if the light unit is set too high, or if your skin is extra sensitive due to a skin condition. If it's too intense, the exposure time will be adjusted or you will be given a break. The goal is to gradually increase the exposure during a treatment.
Besides these short-term effects (sunburn), there are long-term effects. Just like with regular sunlight, too much UVA light is harmful. The skin can be damaged by UVA exposure. The main effects of UVA are skin aging and an increased risk of skin cancer. In addition, pigment spots, a kind of freckle caused by UVA light, can develop.PRACTICAL MATTERSPUVA therapy consists of two, sometimes three, light treatments per week, for a period that depends on the skin condition and its response to the treatment. For each treatment, please report to the light therapy desk. If no one is present, please leave your appointment card on the desk and take a seat in the waiting room.
It is advisable to apply an indifferent ointment to any flaky, dry areas at home on the days you are being treated. This will remove the UVA-reflecting flakes, which will enhance the treatment. We will provide you with a prescription for the ointment. Applying the ointment to the areas should not be done immediately before the light therapy, due to an increased risk of burning the freshly applied skin. An hour should be left between treatments, but longer is also acceptable.
During the light therapy "in the closet," you must wear special eye protection glasses. (These are different from the sunglasses discussed above.) You will receive these "cabinet glasses" at the start of the therapy and must always bring them with you to your treatment.
Try to avoid excessive sun exposure during the period of UVA light treatment. Due to the sensitivity of your skin, the risk of sunburn is higher than normal during this period.
Drinking alcohol during the treatment period is not recommended. The 8-mop capsules contain substances that must be broken down by the liver, which, when combined with alcohol consumption, places an excessive burden on it.
Men are required to wear a thong during UVA light treatment.
In general, expanding your family is not permitted during PUVA treatment for either a man or a woman. Therefore, you must ensure you have effective contraception.
To prevent sunburn, it is wise to report any medication you are taking and any changes to it. Not all ointments and medications are compatible with light therapy: some medications can cause an allergic reaction when combined with light. Therefore, you should always inform your doctor of all medications you are taking and ask whether you can continue using any ointments. Also check the package insert: if it states that 'photosensitivity' or 'photoallergic' or 'phototoxic' reactions may occur, then there is a risk of burns or skin reactions. |
