If you take certain medicines, you may also want to take some extra precautions before heading out into the sun. That’s because some drugs have the little known side effect of leaving you more prone to sunburn, and raising your risk of skin cancer. Since many of the medications are commonly used, and even potentially lifesaving, the solution isn’t to stop taking them—it’s to employ some common sense sun-protection measures to safeguard your skin.
The drugs in question include antibiotics, antidepressants and even pain relievers you’d use for something as minor as a headache. “These medicines contain ingredients that may cause photosensitivity, a chemically induced change in the skin that makes it unusually sensitive to sunlight,” says Jill Stegall, a pharmacist at Trinity Health in Waterloo, Iowa.
Photosensitivy 101
There are two forms of photosensitivity: photoallergy and phototoxcity. A photoallergy is an immune response that occurs after you’ve used a medication repeated times. “The sun’s ultraviolet (UV) rays change the structure of the drug, so it’s seen by the immune system as a foreign invader,” explains Stegall. The allergic response—an itchy rash that can have red bumps, scaling, and oozing—usually develops one to three days after taking the drug. The outbreak can spread to all parts of the body, not just the areas that were exposed to sun.
Phototoxicity is more common and occurs when UV rays interact with your medication, causing exposed skin to burn more severely or more quickly than normal—sometimes within just a few minutes. “Some of the phototoxic drugs are dose-dependent, so the higher the dose, the more likely you are to have a reaction,” says Stegall.
Red alert/Burning issue
It’s easy to discount the dangers of a sunburn—after all, the pain, swelling and possibly even blistering usually go away in a few days. But don’t underestimate their impact: Sunburns can do lasting damage to your skin, causing mutations in the DNA of sun-exposed cells that can develop into skin cancer.
At least one drug, the blood pressure medication hydrochlorothiazide, has even been directly linked with an increase in skin cancer as a result of its ability to enhance the harmful effects of sunlight. “A recent study found the risk of developing nonmelanoma skin cancer (the less risky kind) was up to seven times greater in people who took the popular blood pressure drug for more than 10 years. Of course, heart attacks and strokes are far bigger killers than skin cancer, so it’s important to continue taking all medications as prescribed—and improve your sun-protecting behavior at the same time.
Meds that don’t mix well with the sun
There are multiple classes of drugs that cause photosensitivity, and antibiotics are one of the “worst offenders,” reports Stegall. Here’s a list of the meds she says are particularly problematic.
- Acne medications: sulfa drugs like sulfamethoxazole/trimethoprim (Bactrim, Septra), tetracyclines like doxycycline, minocycline and tetracycline
- Antibiotics: fluoroquinolones like ciprofloxacin (Cipro) and levofloxacin (Levaquin), sulfa drugs and tetracyclines
- Antidepressants: amitriptyline, St. John’s wort
- Antifungals: voriconazole
- Antihistamines: cyproheptadine, diphenydramine (Benadryl), ranitidine, Claritin
- Antipsychotics: chlorpromazine
- Cholesterol-lowering drugs: statins like atorvastatin, provastatin and simvastatin
- Diuretics: furosemide (Lasix), hydrochlorothiazide
- Heart medications: amiodarone, a drug that regulates your heart rhythm. About 10 percent of people taking have a reaction to sun.
- Non-steroidal anti-inflammatory drugs (NSAIDs): ketoprofen, naproxen, piroxicam, ibuprofen
- Oral contraceptives and estrogens
- Seizure medications: lamotrigine, carbamazepine
- Type-2 diabetes medications: glipizide, glyburide
Prescription medicines that are most likely to be photosensitizing often come with a sun sticker, a yellow label bearing an icon of the sun with a slash through it, says Stegall. The fine print of the label reads that you should avoid prolonged or excessive exposure to sunlight while taking the drug. If you’re not sure if the medications you take may make you more sun-sensitive, check with your doctor or pharmacist. Also keep in mind that any photosensitivity risk may still be present once you have stopped taking the medication.
Who’s at risk
There’s no sure way to know if you’re going to be one of the unlucky people who finds out the hard way that their meds don’t mix with the sun. Everyone who takes a photosensitizing medicine won’t have a reaction. Even if you have an instance of sun sensitivity, it doesn’t mean you’re guaranteed to have another if you continue using the drug.
While these types of reactions can happen to anyone, those who are already more sensitive to the sun—including fair-skinned people with light-colored eyes—are more prone to experiencing one.
Protect yourself
If you take these medicines, it’s crucial to be especially diligent about protecting yourself from UV exposure every day, year-round—not just when you’re having fun in the sun. While you’re likely to spend more time outside in the summer, many medications mainly react with UVA rays, which are present with relatively equal intensity during daylight hours throughout the year. And you don’t have to be at the beach or the pool, or even outside, to experience a reaction. “I’ve even seen it happen to someone driving in a car,” says Stegall. That’s because the side and rear windows in a car aren’t specially treated the same way the windshield is to prevent UVA rays from penetrating. Salon tanners should take note too. Exposure to the UVA light used in tanning beds can also trigger these reactions.
To keep from seeing red, heed this advice:
- Avoid prolonged exposure to sunlight, especially between the high-intensity hours of 10 a.m. and 2 p.m..
- Wear sun-protective clothing, including wide-brimmed hats, sunglasses and long-sleeved shirts and pants made of tightly woven fabric.
- Apply a broad-spectrum (meaning it protects against both UVA and UVB) of at least SPF 30 or higher sunscreen to all exposed skin every day. Be sure to reapply every two hours or more if you’re swimming or sweating—even if you’re using water-resistant sunscreen.
If you still experience a photosensitivity reaction despite taking these precautions, don’t stop taking the drug without talking to your doctor first. “Avoid any more sun exposure and consult with your doctor, who may reduce the dose or switch you to a different medication,” says Stegall.
