Watch out for Notable Photosensitizers

Certain supplements increase sun sensitivity – just like some drugs. Remind patients to be vigilant about sun protection as the summer sun scorches on, and to avoid these ingredients if they plan to be in the sun.

The idea of fig as a sun sensitizer might surprise some patients. But it’s well-documented – the fig leaf contains psoralens, which make the skin more sensitive to ultraviolet (UV) light. Psoralens are found in some drugs used for psoriasis phototherapy treatment. Many cases of sun sensitivity from fig leaf have been reported. In at least two cases, the burns were serious enough to require hospitalization. Tell patients to stay out of the sun if they’re using any topical fig products.

Talk to patients about glycolic acid. It’s widely used in OTC topical anti-aging products, and it’s a popular treatment administered by dermatologists. While there’s evidence that it improves wrinkles and sun damage, it can also increase sensitivity to the sun. This can increase the risk of sun damage and skin cancer. Tell patients to avoid sun exposure or to wear protective clothing and sunscreen if they must be in the sun after use.

Finally, remind patients taking St. John’s wort to be cautious. Both topical and oral St. John’s wort can increase sun sensitivity. The average threshold dose range for an increased risk of sensitivity seems to be 1.8-4 grams St. John's wort extract or 5-10 mg hypericin, its main active constituent, daily. And this risk seems to be greater for female patients – make sure they are aware of this risk.

Check out our new monograph class filters to learn about other photosensitizers, including bergamot, lactic acid, and lemon.