Posted on July 19, 2017
Few people are aware that many common medications can intensify the effects of sunlight, greatly raising the risk of burning, rashes, and other skin problems, even after only a short time in the sun.
Most of us know very well that too much time in the sun puts our skin at risk. But did you know that it’s even more important to limit sun exposure when you’re taking certain prescription and over-the-counter medications?
Some medicines contain ingredients that may cause photosensitivity, which is a chemically-induced change in the skin. Photosensitivity makes a person sensitive to sunlight and can cause sunburn-like symptoms, a rash, or other unwanted side effects. It may also be triggered by products applied to the skin or injected medications.
So, What Happens?
One of two things can happen when you take certain medications. The first is known as a photoallergic reaction and occurs when a certain medicine or substance is applied to the skin. Ultraviolet light from the sun transforms the substance in a way that agitates the immune system, leading to irritated skin and eczema-like rashes. The onset of visible symptoms is usually delayed 24 hours to several days.
The second, and far more common reaction, is a phenomenon called phototoxic reaction. This occurs when a person ingests a specific drug or substance and then spends time in the sun. Exposing the skin to ultraviolet rays excites molecules of the ingested substance, causing damage to tissue, like severe redness and sunburn, that is apparent immediately.
Dermatologist Lorraine Young, a clinical professor of medicine at the University of California, Los Angeles, explains that the most common outcome of photosensitivity is an exaggerated sunburn, but warns that other medications may cause immediate burning. “Your sunburn will be redder, more painful, more widespread—a worse sunburn, as if you were out in the sun longer than you actually were,” she says.
In addition many drugs also up your risk of heatstroke, a dangerous condition that requires immediate medical attention. They do this by reducing your body’s ability to sweat, increasing the amount that you urinate, and decreasing your thirst so that you’re less likely to drink an adequate amount of fluids, says Kirby Lee, an associate professor of clinical pharmacology at the University of California, San Francisco. “Heatstroke symptoms can come on quite rapidly, especially in older adults, who often take more than one medication that raises their risk of overheating.”
The Common Culprits
Here’s a list of some of the better-known substances that may allow summer’s sun and heat to hit you much harder:
- Antibiotics, including tetracycline (Wesmycin), doxycycline (Vibramycin), fluoroquinolones (Cipro), levofloxacin (Levaquin), and sulfonamides (Bactrim, Septra);
- Nonsteroidal anti-inflammatory drugs (NSAIDs), including ibuprofen (Advil and Motrin) and naproxen (Aleve);
- Diuretics such as furosemide (Lasix), bumetanide (Bumex), and hydrochlorothiazide (HCTZ, Microzide);
- Beta-blocker medications such as metoprolol (Lopressor, Toprol XL), atenolol (Tenormin), labetalol (Normodyne, Trandate), and carvedilol (Coreg);
- Cardiac or blood pressure medications such as amiodarone (Cordarone) and quinidine; calcium channel blockers such as nifedipine (Procardia) and diltiazem (Cardizem); and ACE inhibitors such as enalapril;
- Tricyclic antidepressants, including amitriptyline (Elavil), nortriptyline (Pamelor), doxepin (Sinequan), and imipramine (Tofranil);
- Antihistamines like diphenhydramine (Benadryl);
- Anticholinergic drugs, such as Vesicare, that treat incontinence, overactive bladder, and many other conditions;
- Antipsychotic drugs like haloperidol (Haldol), olanzapine (Zyprexa), quetiapine (Seroquel), and risperidone (Risperdal);
- Stimulants such as methylphenidate (Ritalin) and dextroamphetamine (Adderall);
- Decongestants such as pseudoephedrine and phenylephrine (Sudafed);
- Diabetes drugs such as glyburide (DiaBeta);
- Cancer chemotherapy drugs such as 5-fluorouracil (5-FU), vinblastine (Velban, Velsar), and dacarbazine (DTIC-Dome); and
- Supplements such as St.-John’s-wort and ginkgo.
For a full list of possible medications, click here.
Fortunately, AARP provides a list of the ways you can reduce the risk of sun-sensitive side effects that accompany these drugs.
Learn and label: Review your current medications with your doctor or pharmacist to learn which, if any, put you at risk. Investigate alternative drugs at the same time. To easily keep track of which of your medications may cause problems, mark each label with a sun symbol so that you see it every time you pick up the container.
Consider substitutes: You may be able to avoid or lower your risk of sun and heat complications by switching to a different medication. Instead of ibuprofen, for example, choose acetaminophen (Tylenol). Benadryl can be replaced with Claritin or Zyrtec, though both should only be taken as needed and in the smallest effective dose. Check with your doctor before you switch to a new medication.
Dress appropriately: Cover up if you’re on these medications and you know you’ll be in the sun. Wear loose-fitting clothes that cover your arms and legs and put on a hat to cover your head and shade your face. If necessary, carry an umbrella. However, don’t “overbundle,” which may cause you to overheat.
Apply the right sunscreen…and in the right amount: Most doctors recommend you choose a 30 SPF sunscreen, or higher, with a “broad spectrum” label. That means it will block the type of ultraviolet rays that react with drugs as well as those that cause sunburns. The proper amount to apply is at least 1.5 ounces, equal to a full shot glass. Sunscreen should be applied approximately 20 minutes before going outside and reapplied every couple of hours if you’re out in the sun and active.
Try to plan ahead: If you know you’re going to be outside and on the move, schedule your activities to avoid the worst time of the day when it comes to heat and UV rays—between 10:00 a.m. and 3:00 p.m. Focus on early mornings or late afternoons/early evenings for the majority of outdoor plans.
Stay hydrated, but don’t overdo it: Water and sports drinks will help keep your body cool, but be careful not to drink too much of either if you have high blood pressure or low levels of sodium. Ask your doctor about how much you should drink. Also, avoid alcohol and caffeine—both are diuretics and will work against your efforts to hydrate.
If you happen to become the victim of photosensitivity, Christopher McCoy, a clinical specialist and professor of pharmacy at Northeastern University’s College of Health Sciences, says treatment will most likely include stopping the offending drug and avoiding exposure to direct sunlight by wearing clothing and UVA/UVB blocking sunscreen for at least two weeks. Physical sunscreens such as those containing zinc or titanium oxide are preferred because chemical sunscreen may exacerbate the reaction. Cool, wet dressings may also help soothe the irritated skin. Oral antihistamines such as diphenhydramine and topical corticosteroids such as hydrocortisone may also provide relief of some symptoms. In extreme cases, corticosteroid therapy with prednisone, an oral tablet, may be required.
The most important lesson to take away here: Ask your doctor questions when you receive a prescription for a new drug and carefully review the written information provided by your pharmacist. If further questions or concerns arise, your doctor or pharmacist is only a quick phone call away.
If you have questions about any healthcare issue, contact the primary care providers at Coastal Carolina Health Care by calling (252) 633-4111 or visiting www.cchchealthcare.com.
(Sources: U.S. Department of Health and Human Services; Federal Drug Administration; AARP; The New York Times; The Skin Cancer Foundation; Scientific American Magazine; Health.com; Consumer Reports Magazine; and United Press International.)