You may know that taking some antibiotics and acne medicine can trigger skin sensitivity to the sun, but common over-the-counter meds like aspirin and antihistamines can also spark sunburns and rashes.
Medications with a possible sun sensitivity side effect are prescribed for a wide range of conditions including allergies, arthritis, depression, diabetes, hypertension, and rosacea. You may have gone through this reaction, which doctors call “photosensitivity.”
What Is Photosensitivity?
Photosensitivity happens when a substance like medication makes your skin sensitive to sunlight. The drug combines with the sun’s ultraviolet light (both UVA and UVB) and creates toxic and inflammatory reactions that harm your skin cells. Drug-induced photosensitivity is widely felt and can even affect those taking certain heart and chemotherapy medications.
There are two types of photosensitivity:
Phototoxicity: A sunburn-like effect that appears only on the skin that has been exposed to the sun. It can show up hours later and it’s the most common type of sensitivity.
Photoallergy: An allergic reaction that can affect areas of the skin that have not been in the sun. It can look like redness, scaling, itching, blisters, or spots that resemble hives. The signs typically develop 24 to 72 hours after you’ve been in the sun and can remain even after you’ve stopped taking the medicine.
Who Is Sun Sensitive?
Your doctor may let you know about the possibility of sun sensitivity, but there is no way to predict which patients will feel it. People can take the same dose of the same medication, and some may be fine in the sun while others break out and burn.
“Drug-induced photosensitivity affects all individuals, regardless of skin color, though the skin findings may appear milder in darker-skinned individuals,” says Vicky Zhen Ren, MD, assistant professor of dermatology at Baylor College of Medicine in Houston. For example, if your skin is darker, the redness seen in lighter skin may show up more as purple.
The darker your skin, the greater the amount of melanin (a substance that absorbs harmful ultraviolet rays) it has.
“Patients with darker skin aren’t as likely to experience the phototoxic side effects because the more melanin in their skin gives them a little more protection, but there is still a risk. Everyone should take the same precautions even if they have less risk,” says Elizabeth Messenger, MD, an assistant professor of clinical dermatology at the University of Pennsylvania’s Perelman School of Medicine.
When to Call Your Doctor
Pay attention to your body if something doesn’t look or feel right on your skin.
“If you have any questions or concerns, ask the doctor who prescribed the medication,” Messenger says. “Your doctor may know how to handle the side effect and would tell you if and how urgently you might need to see a dermatologist.”
Your sun reaction could be more than a rash and you could start feeling ill. If you get flu-like symptoms (fever with chills, nausea, headache, and weakness), or if your skin blisters, see your doctor.
Shield Your Skin
Staying out of the sun is your best bet. If you must spend time outdoors, scope out the shade whether from trees, umbrellas, or awnings. If you plan on being outside, skip the sun between 10 a.m. and 4 p.m., the peak hours for UVB radiation exposure.
Blocking the Sun
The sun’s rays can even reach your skin through windows in your home, workplace, or car.
“Traditionally we think of sunburn when we go outside, due to UVB radiation. But with a phototoxic reaction, a large cause is UVA radiation and it can penetrate through glass. Driving in a car, you normally wouldn’t experience any sun reaction, but it could be different if you are incredibly sensitive to the sun on your medication. Be diligent with your sun protection,” Messenger says.
Dermatologists recommend using SPF 30+ sunscreen that is broad-spectrum (protects against both UVA and UVB light), water-resistant, and contains at least 8% zinc oxide, as well as SPF 15+ lip balms.
“To cover your entire body, adults should apply 1-2 ounces (or 2-4 tablespoons) of sunscreen 15 minutes prior to sun exposure and every 2 hours after – more frequently if you are swimming or sweating excessively,” Ren says.
If you’re nowhere near doing that, you have a lot of company.
“We know that most patients only use 50% of the amount recommended for their body and people don’t reapply it as often as they should,” Messenger says. “You can extend protection with a wider brim hat and long sleeves shirts and pants with a tight weave because it is harder for the sun to go through.” You can also look for SPF 40+ clothing and UV-blocking sunglasses, Ren says.
Caring for Your Skin
If you need relief from irritated skin and minor sunburns, Ren suggests taking cool showers, using plain petroleum jelly or moisturizer containing aloe vera, and drinking plenty of water.
“There are many ingredients in over-the-counter skin care products that might further irritate the skin and cause sensitization that leads to an allergic reaction,” Ren says. “Try to avoid products containing fragrance additives, formaldehyde, lanolin, oxybenzone, or methylisothiazolinone. Sunscreens containing zinc oxide and titanium dioxide are less likely to cause skin irritation.”
Can you still use a retinol product or get facials?
That might not be a great idea.
“Retinols, retinoids, and facials may all cause skin irritation, which can lead to further photosensitivity,” Ren says.
Her advice: “It is best to consult with your board-certified dermatologist or licensed aesthetician regarding the pros and cons of using retinols or undergoing facials based on your skin type, medications, and underlying medical conditions.”
If you opt for such cosmetic treatments, it’s even more important to be strict about sun protection.
“Put on sunscreen to leave home every morning and make it part of your routine,” Messenger says. Everyone needs to do this, regardless of any medications they take. It’s just like brushing your teeth: a habit to keep.
“You don’t realize how much sunscreen does for you until you have a problem when you don’t use it,” Messenger says. “Build daily habits of safe sun practice and you’ll benefit in the long run.”