Photosensitivity: why your skin could be sensitive to sun

23rd June, 2022 • 12 min read

There are few things as cheering as opening the curtains to a sunny morning but if you have a health condition, or if you’re taking certain medicines, good weather can also bring with it worry about how your skin might react to the sun. That’s because certain conditions and medications are linked with photosensitivity.

Also known as sun allergy, photosensitivity is when your skin is over-sensitive to sunlight. It’s usually the sun’s ultraviolet (UV) rays that are responsible, not the heat rays.

Photosensitivity shows up in the form of redness and inflammation on patches of your skin that are exposed to sunlight. There are different types of photosensitivity and depending on which you have, your symptoms can last from a few minutes to a few weeks. You can usually treat it in a similar way to how you’d treat sunburn as long as your reaction is not severe. Otherwise, always get medical help.

Here, we explore 5 reasons why your skin might be more sensitive to the sun and what you can do to manage it. So with a bit of know-how and some self-care techniques, glorious weather can be something you come to enjoy, not dread.

1. Eczema

WHY?

First, some good news: the sun can be beneficial if you have

eczema
. If you have contact or discoid eczema, for instance, you might see an improvement in your symptoms when the sun’s out. Why? Because eczema is an inflammatory condition and the sun has an anti-inflammatory effect.

But some people with eczema may not deal with the sun well. When it’s hot, your skin can become redder and itchier, and if you sweat it can also cause a

heat rash
. This can make your eczema symptoms worse.

Eczema can also be the direct result of exposure to the sun’s UV rays and this is known as ‘photosensitive eczema’. But this type of eczema isn’t common.

WHAT YOU CAN DO

To get the best from the sun when you have eczema, follow these steps:

  • moisturise before applying sunscreen – the sun can dry your skin so apply your usual moisturiser at least 30 minutes before your sunscreen. Go easy if your moisturiser is oily or greasy (do a patch test first if you’re not sure) as this can cause a ‘frying’ effect, which can lead to sunburn
  • get sunscreen savvy – try mineral-based sunscreens which reflect UV radiation. These can be less irritating if you have eczema than chemical sunscreens that absorb UV radiation. Look for titanium dioxide or zinc oxide on the ingredients list. Go for sunscreen free of alcohol and fragrance as both can irritate your sensitive skin. Always choose sun protection factor (SPF) 30 or higher and ‘broad spectrum’, which gives you protection from both UVA (linked to skin ageing) and UVB (linked to skin burning) rays
  • test first – trying a new sunscreen? Test it first and look for allergic reaction in the form of redness, rash, itching, pain and/or flaking. Put a pea-sized amount in the crook of your elbow and wait 24-48 hours before washing that area
  • it’s all in the technique – apply sunscreen in smooth, downward strokes. Rubbing it in can trigger itchiness

2. Psoriasis

WHY?

Is the sun good for

psoriasis
? It depends. On one hand, most people find that scaly red patches (also called ‘plaques’) improve or even clear up when the weather is warm and sunny. But for some, the warmer weather may trigger a flare-up – this is when inflammation ramps up and your psoriasis symptoms get worse.

A small number of people can get something called photosensitive psoriasis. This is when sun exposure leads to a worse psoriasis rash and you might get what looks like sunburn. To control this type of psoriasis, you’ll need to follow strict sun protection along with other treatments. Speak to your doctor or specialist if you’re worried you have this type of psoriasis.

WHAT YOU CAN DO

  • take small steps – for the sun to help with your psoriasis, you need to build up your exposure over time with brief, daily periods in sunlight. Speak to your doctor first to find out how natural sunlight can help your condition. If you expose your skin to the sun for too long, you’re at risk of sunburn, causing injury, and this can result in new plaques forming on your skin
  • be mindful of medications – if you take psoriasis medication such as acitretin and methotrexate, or you’re having phototherapy, these may increase your sensitivity to the sun, so you’ll need to take care with sun protection. Find out more below, about how phototherapy affects your sun sensitivity
  • ace your suncare routine – use sunscreen on all exposed skin, including your plaques. Go for SPF 30 or higher and a product that offers ‘broad spectrum’ protection. Look for sunscreen that’s fragrance-free and is suitable for sensitive skin, too. Remember to do a patch test first (apply a small amount 24-48 hours before sun exposure) to check your sunscreen doesn’t irritate your condition

3. Acne

WHY?

Some people think the sun is good for clearing up their skin, but it can work the other way, too. The sun dries your skin which makes your body produce more oil. As you’ll know if you get

acne
, that’s not great news because the oil clogs your pores and makes acne worse. Sweating in the heat can have the same effect.

Yet you might find that a short spell outside improves your acne as the sun’s warm rays have an anti-inflammatory effect. A small study from Cancer Research UK found that around 9 minutes of lunchtime sun every day during summer is enough for your body to have healthy vitamin D levels through the year, while for people with darker brown skin, such as those of South East Asian origin, it’s around 25 minutes. But keep your time in the sun brief as longer periods spent in sunshine can block your pores.

WHAT YOU CAN DO

  • pick the right sunscreen – wearing sunscreen is important but if you have acne it needs to be ‘non-comedogenic’. This essentially means the sunscreen won’t block your pores. The label might also say ‘oil-free’
  • know your ingredients – if your bathroom cupboard is packed with products that help your skin look its best, then chances are they contain some of the following: retinols, benzoyl peroxide, alpha hydroxy acids (AHAs). These ingredients can make your skin more sun sensitive so it’s important to take extra care in the sun and use them in the right way. That means taking care in the sun and using sunscreen with at least SPF 30. If you use retinol, apply it before bed, rather than in the morning, so that you’re not immediately exposing your skin to the sun. Again doing a patch test might be good here to test any reactions.
  • watch out for acne medications – isotretinoin, oral contraceptives and some oral antibiotics such as tetracyclines – which may all be prescribed to treat acne – can also cause photosensitivity. If your doctor has prescribed any of these medications, you’ll need to be vigilant about sun protection:
  1. Spend time in the shade between 11am and 3pm when the sun is at its strongest
  2. Be generous when you’re applying sunscreen – think around 6 full teaspoons for your entire body
  3. Apply your sunscreen around 20–30 minutes before heading outdoors

Find useful information on other areas of sun safety with our

complete Guide
.

4. Lupus

WHY?

Photosensitivity is pretty common if you have

lupus
. Figures suggest that about 60% of people with lupus find that it’s made worse by the sun’s UV rays. Here’s why: UV light is damaging to everyone’s skin cells, but if you have lupus your cells are way more sensitive to that damage. Your immune system takes longer to clear those damaged cells and your infection-fighting antibodies wrongly target healthy cells, causing an immune reaction.

Also, UV light can trigger lupus flare-ups, bringing on symptoms like fatigue, numbness, tingling and joint pain.

WHAT YOU CAN DO

  • go high – if you have lupus you may need to use a very high SPF of at least 50 when you’re out and about to avoid a photosensitive reaction
  • wear protective clothing – when you’re outside, wear long-sleeved tops and loose-fitting bottoms which cover your skin, made from lightweight, tightly-woven fabrics. Try holding an item of clothing up to the light – if you can see through it, chances are UV rays can easily get through and potentially harm your skin
  • accessorise – it can also be a good idea to wear a wide-brimmed hat and wraparound sunglasses to ensure you’re fully protected against the sun’s UV rays
  • protect yourself at home – consider kitting out the windows in your home with UV-blocking shades to stop sunlight from streaming in

5. Medication

WHY?

Did you know there are more than 100 types of medicine that can make your skin more sensitive to the sun? This type of photosensitivity is called chemical photosensitivity and it can happen with drugs you take orally or those you apply to your skin.

When it comes to chemical photosensitivity, there are two main ways in which you can be photosensitive: phototoxicity and photoallergy.

  • phototoxicity – the most common reaction and it happens when a medication you’ve taken orally or applied on your skin is activated by exposure to the sun. Your skin might look sunburnt or you may have a rash and it’s usually just on the skin that has been exposed to the sun
  • photoallergy – a rarer reaction, this happens when the sun’s UV rays interact with the ingredients in your medication. You might get a rash, blisters, red bumps or oozing wounds

Medications that can make you sun sensitive

More common

Phototoxicity is most common with drugs including:

  • amiodarone for irregular heartbeat – risk of photosensitivity can be more than 1 in 10 people taking the drug
  • tetracycline antibiotics – these are often used for bacterial infections and skin conditions such as
    rosacea
    and acne. The most common type of tetracycline that causes photosensitivity is doxycycline, which may happen in more than 1 in 10 cases
  • anti-inflammatory drugs – these are used for rheumatoid arthritis, gout and other conditions, and phototoxicity is most common with Naproxen. Ibuprofen is another anti-inflammatory drug but it’s unlikely to cause photosensitivity
  • chlorpromazine – this is often used for conditions like
    schizophrenia
    and
    bipolar disorder
    . Photosensitivity is more likely to happen with higher doses so you would be advised to avoid direct sunlight
  • phototherapy (PUVA) for psoriasis – PUVA (psoralen+UVA) is a common culprit for photosensitivity as its job is to temporarily sensitise skin to UV light to help treat skin conditions like psoriasis. On treatment days you should wear long sleeves and a hat as well as SPF 50+ sunscreen. Steer clear of sunbathing for the whole duration of your treatment

Photoallergy may happen with:

  • carbamazepine for epilepsy and nerve pain – photosensitivity may happen in less than 1 in 10,000 cases
  • thiazide diuretics such as bendroflumethiazide – medication used to control blood pressure, photosensitivity may happen in 0.1–1% of people
  • quinine – used to treat leg cramps and malaria
  • sulfonylureas – treats type 2 diabetes

More rare

Photosensitive reactions can happen with other drugs too, but don’t worry, they’re not very common. Examples include:

  • ciprofloxacin – an antibiotic for serious infections, ranging from ear infections to
    sexually transmitted infections (STIs)
    , or when other antibiotics haven’t worked. Photosensitivity occurs in less than 1 in 10,000
  • antihistamines
    e.g. cetirizine
  • cholesterol-lowering drugs e.g. simvastatin
  • oral contraceptives and oestrogens

Did you know your sunscreen could cause sun sensitivity?

Yes, it sounds counterintuitive but for a small number of people, their sunscreen can actually lead to increased sensitivity to the sun. It’s down to the sunscreen’s ingredients but the most common culprit, para-aminobenzoic acid (PARA) isn’t used often in sunscreens anymore.

WHAT YOU CAN DO

  • check with your doctor or pharmacist and read the label before you take any medication to find out whether it might make you sun sensitive
  • you might need to stop taking any medicine that’s causing a photosensitive reaction but always speak to your doctor first

When to see a doctor

Speak to your doctor if you think you’ve had a photosensitive reaction. It’s best to see a doctor if you develop a rash that:

  • affects a very large area of your skin
  • is getting more red, more painful or spreading fast
  • not going away or keeps coming back
  • blistered

You should see a doctor if you feel very unwell, develop a fever or signs of heat exhaustion that don’t get better once you cool down.

How to treat photosensitivity

The best way to stop photosensitivity happening is to avoid your triggers in the first place and to follow the smart suncare tips mentioned above. You may also be advised to use a specially formulated sunscreen.

If you do get a photosensitive reaction, treatment depends on the type of reaction and any other conditions you have. Your doctor may arrange a patch test to find out which product is causing your photosensitive reaction, for example, if they suspect it could be your sunscreen.

If you get a photosensitive reaction to a drug you’re taking, you might be advised to stop taking that drug. But make sure you get advice from your doctor first and be aware it can take many months for your symptoms to get better after stopping.

Treatment may include:

  • applying a steroid cream to your skin to reduce inflammation and irritation
  • antihistamines
  • oral steroids for more severe reactions
  • seeing a specialist for further treatment such as immune-suppressing medications

Self-care tip

In some cases, you can treat your reaction as you would sunburn – for example, use a cold compress on the affected area and use a gentle moisturiser.

Read more about

rashes that can be triggered by the sun
.

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.