Some medicines can cause (serious) skin reactions when you are being exposed to UV light from the sun or an artificial light source. The FAMHP wants to inform you about this issue.
The FAMHP would like to draw your attention to (i) the existing forms of light-provoked hypersensitivity that may occur after using some common medicinal products, (ii) the notifications the FAMHP has received on this subject and (iii) the precautions to be taken in this respect.
Photosensitivity
Certain medicinal products increase your skin's sensitivity to UV light from the sun or by artificial light sources such as sunbeds or high-power halogen lamps. These medicinal products are called ‘photosensitising medicines’ and may provoke photodermatoses: skin conditions caused by or aggravated by UV rays.
Two types of mechanisms are known to trigger photosensitisation: either phototoxicity or photoallergy. In some cases one and the same medicinal product may cause both types of reactions.
Phototoxic or non-allergic reaction
• This is the most common reaction. It resembles a strong sunburn, sometimes with blistering.
• Occurs quickly after exposure to UV rays and is usually limited to exposed skin.
• Symptoms: direct skin damage caused by photoreactivity, i.e. the interaction between the photosensitising substances and light.
• The extent of the reaction depends on the dose of the medicinal product. With good protection against UV rays, patients can often continue using their medication.
• Once you’ve stopped using your medication, skin lesions do not tend to return when you are exposed to UV rays again.
Photoallergic reaction
• This phenomenon occurs less frequently than phototoxic reactions and it occurs more slowly, often after repeated or prolonged use of the medication. Hence it is more difficult to establish the causal link between this skin reaction and the medication used.
• The reaction occurs a few days to even weeks after exposure and can spread to areas of skin that have not been directly exposed to sunlight.
• This is an immune reaction that is only triggered when your skin is exposed to light.
• Possible skin reactions include eczema-like rashes or eruptions with blisters.
• In rare cases, sunlight can trigger a recurrent reaction that continues even after stopping the medicinal product.
Which medicinal products are concerned?
From the long list of medicinal products that may cause skin reactions when exposed to UV radiation, we selected a few examples of commonly used medicinal products. Light sensitivity may occur both in cases of systemic administration (e.g. tablets, capsules, injections) as well as in cases of topical application (e.g. creams, ointments, gels).
• Antibiotics (e.g. tetracyclines – more with doxycycline than with minocycline and quinolones).
• Antidiabetics (e.g. hypoglycemic sulfonylurea agents).
• Antimycotics (e.g. itraconazole, voriconazole and posaconazole).
• Psychotropic substances (e.g. phenotiazine, carbamazepine, fluoxetine and St. John's wort).
• NSAIDs (non-steroidal anti-inflammatory medicines), either for systemic use (e.g. piroxicam) or topical use (e.g. gel-borne ketoprofen).
• Immunomodulators (e.g. tacrolimus and pimecrolimus).
• Medications for the treatment of cardiovascular diseases (e.g. amiodarone, fibrates, thiazide diuretics and Loop-of-Henle diuretics).
• Medications for treating osteoarticular disease (e.g. methotrexate).
• Acne medicines (e.g. retinoids and benzoyl peroxide).
In both the package leaflet and the summary of product characteristics (SmPC) it is always clearly specified whether a medicinal product might cause light sensitivity or other skin reactions.
Precautions
• Avoid direct sun exposure between noon and 4 PM, when UV radiation is strongest. Keep in mind that sunlight reflects strongly on water, sand and snow.
• Use a sunscreen with a high protection (SPF 50+).
Be careful, sunscreen is not always sufficient to prevent photosensitivity.
• Wear long-sleeved protective clothing (such as a long-sleeved t-shirt and long pants), sunglasses and perhaps a wide-brimmed hat.
• If possible, consult your physician to consider switching your medication to another product.
• Avoid using multiple photosensitising medicines at the same time, as this increases the risk of photodermatosis (skin reactions caused by exposure to UV rays).
• Healthcare professionals (physicians and pharmacists) should warn patients about the risk of exposure to sunlight and artificial light sources such as sunbeds, halogen lamps or boosted lamps in operating theatres or dentists’ offices.
• If you notice any symptoms of photodermatosis (such as rash or blisters), please consult your physician to consider stopping the use of the medicinal product that may be the underlying cause.
More information for patients can be found on the website PharmaInfo.
If you have any questions or doubts, please always consult your physician or pharmacist.
Notifications to the FAMHP
Over the past decade, the FAMHP has received several notifications of photoallergic or phototoxic reactions for several medicinal products, including:
• non-steroidal anti-inflammatory medications (NSAIDs, e.g. ketoprofen - 15 notifications);
• tetracyclines (e.g. doxycycline - 5 notifications);
• anti-tumor medications (e.g. brigatinib, alectibib, baricitinib, ribociclib - 11 notifications);
• medications for the treatment of cardiovascular diseases (e.g. perindopril, amiodarone - 4 notifications);
• immunomodulators (e.g. dupilumab, vedolizumab, adalimumab, ixekizumab - 9 notifications);
• medications for the treatment of pulmonary fibrosis (e.g. pirfenidone - 3 notifications);
• antihistamines (e.g. desloratadine - 2 notifications).
These were notifications of suspected side effects. This means that they refer to medical events that occurred after using the medicine, but which were not necessarily caused by the medicine itself.
Notifications of side effects
Patients and healthcare professionals are encouraged to report any suspected side effects on our website.
More information is available on the FAMHP website.
You can read the package leaflet as well as the SmPC via the FAMHP’s medicines database.