Sun is shining, the weather is sweet – and we are well aware of the need for sun protection.

But, it’s not just SPF that requires our full-attention, the hot-weather months call for a deep-dive into our summer beauty shelf altogether. 

Why? Certain products from make-up to perfume, can pose a more sinister side when exposed to high UV levels, shifting into gear phototoxicity and photoallergic reactions.

Beauty is not as clear cut as being anti this or pro that though, as the behind-the-scenes complexity of it revolves around formulations and concentrations as much as ingredients.

Understanding the key factors and red flags will help to summer-proof your beauty regime and keep skin extra safe in the sun.

Phototoxicity reactions skincare high UV

Phototoxic reactions are a common type of photosensitivity reactions – often red, itchy, sunburn-like skin rashes that appear when exposed to the sun.

Results from clinical trials show 29 per cent of people tested, suffered phototoxic reactions. Of those, 18 per cent experienced adverse reactions to fragrance and 13 per cent to antimicrobial agents. 

This is often a result of topical or oral products absorbing the light and causing direct cellular damage, due to certain ingredients. 

Known as drug-induced photosensitivity (DIP) – a common adverse drug reaction – another form is photoallergy. This happens when the interaction between drug and UV causes an immune cutaneous reaction such as eczema or psoriasis. 

But, while photoallergic reactions are delayed, phototoxicity is immediate and can appear as an exaggerated sunburn rash, raised spots or in some cases, blisters. They typically clear up once the triggering product is halted.

Phototoxicity reactions skincare high UV

Awareness of certain ingredients often piques through circulating trends and buzzwords-of-the-moment. But, an important factor that should always bring alertness is the weather. 

The traditional ritual of Spring-cleaning your home come the new season is just as beneficial to your skincare routine – as products that work wonders during the winter can react differently in summer.

There are a few gangs that are not always all-year-round helpers. Ones to watch are fragrances, essential oils and chemicals such as Benzoyl peroxide – commonly used in acne-removal creams. These are known irritants that can sensitize skin. 

Many perfumes and scented products such as deodorants – as well as natural deodorants – contain compounds such as Limonene, which can cause aggravation during summer. It smells nice, but oxidises in the air and can therefore cause allergic contact dermatitis and counts as a frequent skin sensitiser. 

Even products that are branded ‘unscented’ can have other fragrant irritants to mask the fragrance. Making it tricky to decipher inci lists.

Phototoxicity reactions skincare high UV

Natural or green products can also be culprits of phototoxic reactions and irritations, due to their inclusion of essential oils. These oils are extracted from flowers, bark, stems, leaves, roots and select fruits through either distillation or cold-pressing and are usually highly concentrated.

Citrus oils in particular, such as citrus grandis peel, include the problematic compound called furanocoumarin – an organic plant extract that makes beauty products mildly phototoxic. It can sometimes be found in vitamin C focused make-up products. 

Other citrus ingredients that can react with UV light and result in sun-damage symptoms include lemon, lime, orange, bergamot, cumin, ginger, and verbena.

Retinoids require attention too. Derived from vitamin A, they have the potential to absorb light and act as photosensitisers. Though usually, this is a result of enhanced skin irritancy. The potent formula can make skin more sensitive to light and sunburn. Therefore, it’s always best to use at night, invest in a rich moisturiser and wear factor 50 SPF at all times.


Typically, furanocoumarin occurs in mostly cold pressed citrus oils such as bergamot, bitter orange, grapefruit, lemon, lime and mandarin.

But, you can get bergamot essential oil with the furanocoumarin removed; many brands use this instead. In addition, steam distilled citrus essential oils don’t have the same issue.

There are tight regulations around the use of phototoxic constituents in essential oils. 

Maximum limits are set to prevent phototoxicity issues and all cosmetic products need to pass a safety assessment that looks at the combined percentages of troubling constituents. This is to ensure the threshold hasn’t been crossed if multiple essential oils are being used.

For this reason, it’s best to avoid DIY products with recipes you find online or buy unregulated cosmetics.

Phototoxicity reactions skincare high UV

While it’s important to be aware of potential irritating ingredients, it’s also important to know what could make a reaction more likely.

The susceptibility of your skin can be put down to the concentration of the ingredient, how long it is applied to skin and whether the product is left on for long periods or rinsed off straight away.

Another important factor is the status of your skin barrier and microbiome.

The skin barrier is the first-to-cross shield irritants have to battle through to cause disruption. If this is compromised, it’s already more sensitive and likely to have an adverse reaction. 

Particularly those with eczema, psoriasis or rosacea will likely be more responsive to fragrances and essential oils. 

But, it’s important to note, that a reaction will not necessarily trigger after just one use – it could more likely happen during a flare-up, and heightened further during high UV exposure.

Phototoxicity reactions skincare high UV

A little dig around will show you that these ingredients are often in a lot of products, especially those that are labelled ‘natural’.

Your daily go-tos may have a few culprits lurking in your make-up collection or even deodorant bottle. 

If you are frequently experiencing reactions to skincare – or beauty products in general – then it’s best to pause your regular routine. Chances are, you may have a compromised skin barrier and an imbalanced microbiome.

Getting accustomed with your skin’s bacteria will help unlock why your skin is reacting how it is. This can be done through our skin microbiome test, a simple cheek swab will present you with a report of the bacteria and bugs on your skin and your exact type.

If you have not yet experienced any reaction, but are concerned you may do, then it’s best to always check out the order of the Inci list. Look for the red flags, if they are high up on the ingredients label – as typically they are ordered in highest concentration first – then switch them out of your routine until winter rolls around.

Routines should not only be switched around to suit concerns, but to align with seasons. Just like our moods, our skin reacts and behaves differently depending on the weather.

So, make sure to check in on your beauty habits and give them a seasonal-proof to ensure skin remains healthy and protected.

For a limited time only, we are offering you a chance to trial our award-winning skincare service for free. Click here to learn more.

Phototoxicity reactions skincare high UV