MEDICATIONS MAY INCREASE SENSITIVITY TO SUNLIGHT

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from ScienceDaily.com

Medications May Increase Sensitivity To Sunlight

WEST LAFAYETTE, Ind. - Applying a sunscreen may help protect against the

sun's burning rays, but if you're taking a medication, you may need to take

additional precautions, says a Purdue University pharmacy expert.

Many widely used medications can cause an increased sensitivity to light in

some individuals, resulting in hives, rashes, or other skin eruptions, says

Gail Newton, associate professor of pharmacy practice.

These problems, called photosensitivity reactions, can occur when a person

is exposed to sunlight and other types of ultraviolet light for even brief

amounts of time, Newton says. Exposure to UV light in tanning beds and

indirect sun exposure - such as light reflected off pavement - also can

trigger these reactions.

Though dozens of medications may cause this problem, some of the more

commonly used medications include some antihistamines, used in cold and

allergy medicines; nonsteroidal anti-inflammatory drugs, used to control

pain and inflammation; and antibiotics, including the tetracyclines and

" sulfa " drugs, Newton says.

Other medications containing photoreactive agents include some

antidepressants, antibiotics, anti-psychotics, cancer chemotherapy,

cardiovascular drugs, diuretics and oral diabetes medications. The herbal

remedy St. 's wort, sometimes used to treat depression, also has been

associated with photosensitivity, she says.

" The exact reaction to sunlight exposure depends on the drug being used, "

she says. " With some medications, sunlight exposure can trigger a fine red

rash, with others, patients burn more severely or more quickly than normal. "

Though these drugs do not directly increase the risk of skin cancer,

serious sunburns, particularly in children, have been associated with an

increased incidence of skin cancers later in life, Newton says.

People using these types of medications should take extra precautions in

the sun, Newton says.

" Ideally, people should avoid prolonged exposure to sunlight while using

one of these medications, " she says. " When exposure cannot be avoided,

people should use a broad-spectrum sunscreen with an SPF of at least 15,

preferably 30. "

Newton recommends checking sunscreen labels for the ingredients zinc oxide,

titanium oxide or avobenzone, which protect against both UVA and UVB rays.

" Though most sunburns are caused by UVB rays, some photosensitivity

reactions are triggered by UVA rays, " she says.

Newton says additional precautions include:

* Following the label directions. At least one full ounce - about three

quarter-size dollops - of sunscreen should be applied 30 minutes prior to

exposure. The product should be reapplied after swimming or excessive

sweating.

* Wearing protective clothing. Wide-brimmed hats, sunglasses and

tightly-woven, long-sleeved shirts and pants are recommended.

* Avoiding exposure during the high intensity hours of sunlight between 10

a.m. and 4 p.m.

Though medications associated with photosensitivity often come with warning

labels, Newton says consumers may contact their pharmacist with questions on

the risk of photosensitivity associated with any specific medication.

Editor's Note: The original news release can be found at

http://news.uns.purdue.edu/UNS/html4ever/0009.Newton.photosensitiv.html

Note: This story has been adapted from a news release issued

by Purdue University for journalists and other members of the public. If you

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http://www.sciencedaily.com/releases/2000/08/000807070850.htm