Sun and your medication: medicines that make skin sun sensitive

Which medicines can cause skin reactions in the sun, how to recognise them and what precautions to take if you are on one of these treatments.

Yes, you can enjoy the sun while taking medication, but some medicines make the skin more sensitive to ultraviolet radiation and can cause exaggerated sunburn, dark patches or rashes after exposure that would not normally harm you. Knowing whether your treatment is one of them and protecting yourself properly is enough to enjoy the summer with peace of mind.

A note on terms: technically, these medicines are called photosensitising. In Spanish, "fotosensibles" refers to medicines that are damaged by light, as the Regional Government of Castile and León points out. This article is about the first group.

What is medicine induced photosensitivity?

It is an exaggerated or abnormal skin response to sunlight or artificial ultraviolet sources, caused by a medicine. There are two types: phototoxicity, which is the more common, and photoallergy, which is much rarer.

Phototoxicity increases with the dose of the medicine and the length of exposure. Photoallergy is more common with products applied to the skin.

Which medicines can cause it?

There are many, from very different groups, so the safest approach is to check each medicine's leaflet or ask at the pharmacy. These are some of those listed by the Regional Government of Castile and León and the US FDA:

A medicine appearing here does not mean it will cause you a reaction: it means you should protect yourself. To find the warning for your medicine, check the warnings section of the leaflet, as we explain in how to read the leaflet.

How do you protect yourself if you take one of these medicines?

The protection is the usual kind, but with no exceptions: avoid direct exposure at the hours of strongest radiation, cover up with clothing and use a broad spectrum sunscreen. The Regional Government of Castile and León also recommends avoiding sunbeds and other artificial UV sources.

• Shade and timing: the FDA advises seeking shade, especially between 10 am and 2 pm, and notes that some organisations extend that window to 4 pm. Water, sand and snow reflect radiation.
• Sunscreen: one that protects against UVA and UVB. The FDA recommends SPF 30 or higher and reapplying as directed.
• Clothing: long sleeves, a wide brimmed hat and sunglasses with a UV filter, even in the shade and on cloudy days.
• Anti inflammatory gels: the leaflet for a ketoprofen gel says not to expose the treated area to the sun, even when cloudy, during treatment and for 2 weeks afterwards, to cover it with clothing and to wash your hands thoroughly after each application.

The Regional Government of Castile and León mentions that, if the medicine is necessary, taking it at night may lower its concentration in the skin during the sunny hours. Do not change the timing on your own: ask your doctor or pharmacist first whether it is possible in your case. And if you are travelling somewhere hot, also see how to store your medication in the heat.

What should you do if you get a reaction?

Get out of the sun, protect the area and ask your doctor or pharmacist. Do not stop a prescribed medicine without talking to them first, because it may be important for your health and there may be alternatives.

1. Avoid further sun exposure and cover the affected area.
2. If you use a gel or cream and get a skin reaction, stop applying it, as the ketoprofen gel leaflet says, and seek advice.
3. Book an appointment or ask your pharmacist, and bring the names of the medicines you take, including those applied to the skin and herbal remedies.
4. Seek urgent care if you develop widespread blisters or a fever, or feel unwell.
5. You can report the suspected adverse reaction to the AEMPS through its notificaRAM website, which is also open to the public.

A practical example: Elena before her holiday

Let us take the example of Elena, 56, a teacher. She takes a diuretic for her blood pressure and, for a few weeks, has been applying an anti inflammatory gel to her knee. In July she is going to the beach for ten days.

Before leaving, she reads the leaflets and sees that both mention reactions with the sun. She asks at her pharmacy and organises her holiday like this:

• She keeps taking her diuretic as usual and uses a high factor broad spectrum sunscreen, which she reapplies after every swim.
• She asks her GP about the gel: the GP suggests an alternative for those days, because with a bare knee on the beach it would be hard to follow the leaflet's precautions.
• She plans her walks for early morning and evening, and wears a hat and sunglasses.

Elena enjoys the beach knowing what risks her medication carries and how to avoid them.

How can IMA Health help you?

When your medication is organised and reviewed, it is easier to know what you take and what precautions each medicine involves. At IMA Health we coordinate with a specialised pharmacy that prepares your medication by day and time of each dose, we deliver it to your home and we provide personalised follow-up, so you can raise your questions about your treatment. For questions about anti inflammatories, you may also find what NSAIDs are and how they work useful.

Sources

• Regional Government of Castile and León, Sacylipe no. 6: Medicines and photosensitivity (2016, in Spanish)
• FDA: The Sun and Your Medicine
• CIMA (AEMPS): leaflet for a ketoprofen gel (Fastum 25 mg/g, in Spanish)
• AEMPS: Reporting suspected adverse reactions by members of the public (in Spanish)

This article is for information only and does not replace advice from your doctor or pharmacist.