Allergies acting up? The first instinct for a sufferer might be to crawl back under the covers and away from the light of day.
But staying indoors may not be an option for celebrities who want to remain on the public radar. For public figures such as Jessica Simpson, Scarlett Johansson and Serena Williams, allergies can pose a problem.
"Your nose is running, you are sneezing a lot, eyes are watery and red," said Dr. Marc Riedl, assistant professor of medicine and section head of clinical immunology and allergy at the University of California-Los Angeles. "We hear it over and over from individuals, being in social settings and having the attention on you."
Trying to focus on a job, despite having allergies, can be made even more difficult if exposure to an allergen is in your job description. A movie featuring a cat or dog can pose serious problems for an actor who has an allergy. Riedl said this situation bypasses the first rule of combating allergies: avoiding the allergen.
And having to perform at a certain standard might leave a person with no option but to ignore the allergy or to attempt precautionary measures, such as taking an antihistamine. For example, pro-golfer Tiger Woods plays his way through tournaments, despite a pollen allergy.
Some studies have shown that mood can affect how bothersome allergy symptoms are. In one study, subjects who were watching a funny movie were less bothered by their allergy symptoms than those who watched a sad movie. In general, people who are focused on a task or are enjoying something are less troubled by their allergies.
"Certainly, the symptoms can be influenced by the state of mind," Riedl said.
For those whose allergies are simply a nuisance but not life threatening, however, there may be nothing to do but endure some discomfort until they pass.
"There are many people working in those situations who just grin and bear it," Riedl said. "Regardless of a person's occupation … you can expect there will be an impact on their job and quality of life."
The following is a list of a few celebrities who get the sniffles on the job.
Jessica SimpsonSimpson, 28, has made headlines with her music, her personal life and her food mix-ups.
She rose to fame in the early 2000s with her singing career, but it was her MTV reality show, "Newlyweds: Nick and Jessica," with former 98 degrees star Nick Lachey that made her a household name.
In the first season, Simpson famously asked then-husband Lachey whether her tuna fish was chicken, confusing the food with the Chicken of the Sea brand name. "Is this chicken, what I have, or is this fish? I know it's tuna, but it says [sic] 'Chicken... by the Sea.'"
In that same 2003 season, Simpson learned that Buffalo wings don't come from buffaloes.
The couple split in 2005, ending the successful show. Simpson's habit of confusing foods might do more than damage her reputation. In a 2007 interview by Andrew Goldman in Elle magazine, Simpson revealed numerous food "allergies" more likely to be described as intolerances by allergists.
"She's allergic to cheese. And wheat. Oh, and tomatoes, hot peppers, coffee, corn, and chocolate," Goldman wrote in Elle.
Known for her striking beauty, as well as her rich voice and talent, Scarlett Johansson has made a respectable career for herself at a young age.
Now 24, Johansson had a breakout role at age 13 in the "The Horse Whisperer." But it was her lead role opposite Bill Murray in the 2003 film "Lost in Translation" that put her on the public's radar.
Recently, Johansson has joined with fellow New Yorker Woody Allen to make several films, including "Match Point" in 2005, "Scoop" in 2006 and "Vicky Cristina Barcelona," to be released this year.
It was during the filming of a love scene in "Match Point" that the starlet's allergies came into the spotlight.
In an interview with the BBC, Johansson described dealing with her allergies under Allen's directing:
"He, [Allen] for some reason thinks I'm a hypochondriac, which I find to be absolutely ridiculous. I'm just environmentally sensitive, that's all. Rolling around in a wheat field in the rain is not the best thing for anybody with allergies," Johansson said.
"He said that if my eye swelled to the size of his fist I could have two days off. ... It wasn't so bad, but have you seen the size of his fists? They're not small. It was slightly swollen, but nothing a couple of Allegra D couldn't cure."
The notoriously mercurial British modeling icon Naomi Campbell recently announced that she is no longer drinking because "I find that I'm allergic to alcohol," she said. The San Francisco Gate also reported her saying that she has "more energy and more fun than when I was drinking and I can hang out really late and get up early in the morning with no hangovers and still smile."
According to James Li at the Mayo Clinic, a true allergic response to alcohol is uncommon.
"A true food allergy involves your immune system," Li wrote on the clinic's Web site. "In such cases, your immune system mistakenly identifies a specific food or a component of that food as a harmful substance. Signs and symptoms include hives, breathing difficulties and swelling of your lips, tongue or throat."
But some people can be allergic to specific ingredients in drinks, like wheat. And an allergy could make a person more susceptible to the normal effects of a drink or two.
Campbell also claimed that much of her well-publicized bad behavior is alcohol-related. In 2000, she pleaded guilty to hitting her assistant with a phone and threatening to throw her out of a moving car. Campbell pleaded guilty again in 2007 to hitting her housekeeper. And in 2008 she was accused of spitting on a police officer at London's Heathrow Airport.
Her publicist, Jeff Raymond, declined to answer questions about her allergy.
On the golf course, Tiger Woods is a formidable force against any fellow golfer. But one foe always poses problems on the green.
"The weather will affect him differently than the other guys because Tiger is allergic to every thing on the golf course," Earl Woods, Tiger Woods' father, said in a 2003 interview with The New York Times. "He has taken allergy shots as a kid and he has developed a resistance to everything. But … in the spring, that pollen gets to him."
Woods, 32, has not let his allergies get the better of his game. He has won 86 tournaments during his 12-year professional career.
''We have air purifiers that we put in his house, and in his room, so he can sleep properly and so his allergies won't overcome him,'' Woods said. ''He does not like to play with medicine in his body.''
Funny woman Molly Shannon, best known as a regular cast member on "Saturday Night Live," may be able to induce laughter like nobody's business, but her allergies induce reactions of their own.
"I have bad cat allergies," Shannon, 43, said on the CW11 Morning News in New York. "I'm one of those people if I go to somebody's house, even if I don't see the cat, I start wheezing or I get hives. I'm just very sensitive."
Shannon's father and younger son have allergies as well. She has been a spokeswoman for the Allergy and Asthma Foundation of America, raising awareness about allergies.
Shannon's career at "SNL," where she was the longest featured female cast member and had several recurring roles such as licensed joyologist Helen Madden and quirky Catholic schoolgirl Mary Katherine Gallagher, led to more featured parts in films. But her allergies posed a problem on the set of a recent film, "Year of the Dog."
"I didn't tell them, but we were in preproduction one day and I broke out a little bit because of the dog so I told them and they were like what?!?" Shannon told The Cinema Source magazine. "So I went to an allergy doctor and got all this medication but I never had to use any of it. I'm much more allergic to cats."
Serena Williams has continually wowed the tennis world with her skills, physical prowess and unique style since she rose to fame 10 years ago.
Currently ranked sixth in the Women's Tennis Association, the 5 feet 10 inch' beauty has made media headlines for her wins and her flamboyant fashion on the court.
She and older sister, Venus, have battled for the No. 1 ranking several times since both came on the tennis scene in the late '90s.
Even when a series of leg and ankle injuries led her to drop out of the top 100 ranking in mid 2006, Williams stayed in the spotlight with celebrity appearances, charity work and her fashion designs. Williams started her own fashion line Aneres -- Serena spelled backward -- and says on her official Web site that she hopes to continue with fashion after her tennis career.
But Williams can't beat everything -- she's allergic to peanuts. She falls in the approximately 1 percent of the population with a peanut allergy. According to the U.S. Olympic Web site, Williams says she's also allergic to crazy people.
Drew Barrymore, a gifted and versatile actress, has as eclectic collection of allergies as she does film roles.
Barrymore, 33, is allergic to garlic, according to a 1997 article in the Houston Chronicle, as well as coffee, bee stings and perfume.
Also a vegetarian, Barrymore said that eating "can be a major pain for me."
Barrymore, whose first major role was in Steven Spielberg's "ET" in 1982, and who went through bouts of partying and drug abuse in her adolescence, has blossomed into a career as an established actress and producer with huge box-office appeal.
Though her production company is named Flower Films, flowers and pollen are not among her list of allergens.
If Neko Case wasn't a musician, she knows what she might be.
"If I ever got out of music, I'd go back to school to become a forest ranger," Case, 37, told Fab magazine. "I've always wanted to be the lady with the jeep and the dog who works at the national forest service. I'd let the animals run free."
Her music is rife with animal imagery, but free-roaming animals might pose a problem to Case's forest fantasy because she is allergic to cats.
"I'm both a dog and a cat person, but I've just become allergic to cats in the last five years."
As a solo artist, Case has released seven well-received albums of alternative rock, tinged with country. She's known for her independent spirit, but she is also a member of the Canadian band New Pornographers.
Most people know Alex Kapranos as the lead singer of the rock band Franz Ferdinand, but he's also an exotic foodie. His book about the unusual delicacies that he has eaten on tour includes bull testicles from Argentina and fish brain bread from Finland
Yet for all his daring, there's one food Kapranos won't allow near his lips -- peanut butter, or anything else made from peanuts. He's severely allergic, and has said that he has learned how to ask whether dishes contain any peanuts at all in a multitude of languages.
Peanuts, actually legumes, belong to the same family as alfalfa, clover, peas and lentils.
According to the Mayo Clinic, peanut allergies often appear in the first years of life. And unlike other food allergies, most kids don't outgrow them as they get older.
Symptoms can include mild skin and throat irritations, but some people can experience anaphylactic shock after ingesting the legume.
The National Institute of Health says each year about 150 Americans die from food-induced anaphylaxis. The most severe kind of anaphylaxis is associated with a sudden and dramatic drop in blood pressure and swelling of the bronchial tubes.
Kelis, a Grammy-nominated R&B artist with hit singles such as "Bossy" and "Milkshake," is assertive when it comes to her lyrics. But the singer has failed to be up-front about her allergies in the past.
According to British newspaper The Sun, Kelis, who has a nut allergy, was eating at a restaurant in Zurich, Switzerland, and had an allergic reaction and began to choke.
A friend said "her face went red and puffy and she started spluttering for air. It's dreadful to think what could have happened -– people can be killed by bad reactions to nuts."
To date, there have been no media reports of Kelis having a milk allergy.
Nicollette Sheridan, 44, plays Edie Britt, a conniving housewife, on ABC's "Desperate Housewives." But Sheridan may need to take a break from the perfect flowers on Wisteria Lane, the idyllic suburban street where she and the rest of the housewives live, because of her allergies.
Sheridan reportedly referred to herself as a "Benadrylhead" because the flowers on set were causing her allergies to act up.
"When those exposures happen, you bypass the first principle, which is to try to avoid those environmental exposures," UCLA's Riedl said. "It is bothersome for people who have to be in the spotlight."
Clay Aiken may have the pipes to belt out tunes on Broadway, but his sensitive side comes out often, especially when it comes to food.
The "American Idol" runnerup is allergic to coffee, chocolate, mint, mushrooms, shellfish and nuts.
"I was on a flight one time and the flight attendants were passing out bowls of warm mixed nuts," Aiken said in Starpulse, an online entertainment magazine. "We said 'no' to it, and they wanted to take a picture later and we all got together for a picture and one of their hands touched mine and I had a big welt on my hand."
Aiken, 29, has graduated from the Idol stage to Broadway, where he is now a cast member in Monty Python's "Spamalot."
Lauren Cox and Aina Hunter contributed to this article.
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