Certain Foods, Drugs Don't Mix With Sun.htm

[Guest guest]

Site Map Your Account Support About Us

Offerings: Medscape.com Charts Mobile Logician CBSHealthwatch

FromSkin & Allergy News Certain Foods, Drugs Don't Mix With SunDoug Brunk, San Diego Bureau

[skin & Allergy News 29(9):21, 1998. © 1998 International Medical News Group.]

The next time you're cutting a lime slice to put in your drink at a barbecue, think twice before exposing your fingers to the skin of that lime, or you could wind up with blistering red spots within days.

Lime skin, celery, and many other foods contain psoralens, chemicals that are one of the many culprits in photosensitivity -- an umbrella term for skin reactions caused by certain foods or drugs when combined with sunlight exposure.

No one knows for sure how many people suffer from such ill effects of sunlight, but Dr. DeLeo estimates that between 10% and 15% of Americans have experienced a form of photosensitivity known as polymorphous light eruption at some point in their lives.

"That alone is an incredible incidence," Dr. DeLeo, chairman of dermatology at St. Luke's-Roosevelt Hospital Center in New York City, said in an interview. "If you put all of the photosensitivities together, you're dealing with a very significant problem."

Most photosensitive outbreaks are acute, self-limited problems, so many patients don't seek medical care, or they may get care from a primary care physician and never reach a dermatologist.

Dr. Warwick Morison, professor of dermatology at s Hopkins University in Baltimore, said that primary treatment for photosensitive reactions involves keeping patients away from the agent that triggers the reaction or advising them to steer clear of direct sunlight. "You have to remove one of those two."

Topical corticosteroids, cool baths, and aspirin can provide relief from itching.

There are two main types of photosensitive reactions: phototoxic and photoallergic. A phototoxic reaction occurs when irritating chemicals in food or ingested substances in medications become activated by the sun's ultraviolet rays. Symptoms resemble an exaggerated sunburn and may include erythema, pain, and sometimes blistering; these symptoms can occur from 30 minutes to several hours after exposure. They appear only on areas of the skin exposed to sunlight.

A photoallergic reaction occurs when the sun's rays trigger an immune system response to a medication. Symptoms include scaly, itchy rashes that can appear 1-14 days after exposure. They appear only on areas exposed to sunlight, but severe rashes can extend beyond those areas.

In addition to psoralens, common phototoxins include amiodarone, protriptyline, and tetracyclines -- especially doxycycline. (See box for comprehensive list.)

Common photoallergens include chlorpromazine, sulfonamides, and nonsteroidal anti-inflammatory drugs. An American Academy of Dermatology study in 1991 implicated NSAIDs in 13% of all photosensitive skin reactions reported.

Photosensitive reactions vary widely, regardless of the culprit. "Some data suggest that if you take doxycycline at a dosage of 100 mg a day, it's not going to cause a problem in most patients unless they get excessive sun exposure," Dr. DeLeo said. "But if you double that dose, then you'll have a higher incidence of inducing a problem."

Not every antibiotic triggers such a high-level reaction, however. Dr. Morison said that although "every pharmacist in the United States" warns patients about tetracycline itself as the cause of phototoxic reactions, he considers tetracycline to be an "extremely weak" culprit.

"I can't remember a time that I've seen [a reaction to it]," said Dr. Morison, also in private practice in Lutherville, Md. "You need a giant exposure to sunlight in order to produce problems with tetracycline."

But it doesn't take much sunlight for other drugs to create problems. Dr. Joram Seggev, a Las Vegas-based allergist/immunologist, said that 30%-50% of patients on amiodarone experience a phototoxic reaction when they're exposed to the sun's rays.

Drugs and Chemicals That Can Cause Photosensitive Reactions

Anticancer Drugsactinomycindacarbazine doxorubicin HCl5-fluorocytosinefluorouracilhydroxyureamethotrexateprocarbazinevinblastine

Antidepressants amitriptylineamoxapinedesipraminedoxepinimipramineisocarboxazidmaprotilinenortriptylineprotriptylinetrimipramine

Antihistaminescarbinoxaminecyproheptadinediphenhydramine

Antimicrobials ciprofloxacindemeclocyclinedoxycyclineenoxacinfleroxacingriseofulvinmethacyclineminocyclinenalidixic acidnorfloxacinoxytetracyclinesulfadoxine and pyrimethaminesulfamethizolesulfamethoxazolesulfamethoxazole and trimethoprimsulfasalazinesulfisoxazoletetracycline HCl

Antiparasitic Drugsbithionolchloroquinepyrvinium pamoatequinine

Antipsychotic Drugschlordiazepoxide HClchlorpromazinechlorprothixenefluphenazinehaloperidolperphenazinepiperacetazineprochlorperazinethioridazinethiothixenetricyclic antidepressantstrifluoperazine

Diureticsacetazolamideamiloridebendroflumethiazidechlorothiazidecyclothiazidefurosemidehydrochlorothiazidehydroflumethiazidemethyclothiazidemetolazonepolythiazidequinethazonetrichlormethiazide

Hypoglycemicsacetohexamidechlorpropamideglipizideglyburidetolazamidetolbutamide

NSAIDscarprofenketoprofennaproxenphenylbutazonepiroxicamsulindac

Other Agentsamiodaronecaptoprilcarbamazepineclofibratecyclamate calciumdisopyramideetretinatefenofibrategold saltshematoporphyrinisotretinoinoral contraceptivespromethazinepsoralen derivativesquinidine gluconatequinidine sulfate triacetyldiphenolisatintrimeprazine Source: Dr. DeLeo

INTERACT

Email this article to a colleague.

Site Map Your Account Support About Us

Medscape Search Options

Clinical Content News Info for Patients Medical Images MEDLINE AIDSLINE Drug Info Dictionary Whole Web Dow Library ($)

Select a database to search, enter a search term, then click “go.” Advanced Search Forms

All material on this website is protected by copyright. Copyright © 1994-2001 by Medscape Inc. All rights reserved. This website also contains material copyrighted by 3rd parties. Medscape requires 3.x browsers or better from Netscape or Microsoft.