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Not so long ago, crippling nausea and vomiting were routine for people undergoing chemotherapy. But thanks to new drugs and other treatments, that isn't the case anymore.
"We've made great progress," says Karen Syrjala, PhD, director of biobehavioral sciences at the Fred Hutchinson Cancer Research Center in Seattle. "We have much less nausea and vomiting now -- even though we're using much higher doses of chemotherapy than we did before." Because we can control the side effects, Syrjala says cancer treatment itself is much more aggressive.
Antinausea medications -- or antiemetics -- are so effective, that experts have shifted their focus from treating nausea to its aggressive prevention.
"My standard goal is to stop nausea before it happens," says Christy Russell, MD, chair of the American Cancer Society Breast Cancer Advisory Committee, "rather than waiting for it to start and then treating it."
Of course, not all cases of nausea and vomiting can be prevented -- 70-80% of people on chemotherapy still face some risk. But thanks to better treatment, most people in chemotherapy are able to go about their normal lives, working and caring for their families.
"You may not feel great all the time," says Carmen Escalante, MD, chair of the department of general internal medicine at the University of Texas M. D. Anderson Cancer Center. "But you can keep going. And that's a big improvement on what chemotherapy used to be like."
Chemotherapy Side Effects: How Serious Are They?
For people who have faced it, chemotherapy-induced nausea and vomiting feel like a lot more than side effects. They can be overwhelming, becoming all you think about.
Chemotherapy can cause a number of types of nausea and vomiting.
Untreated nausea and vomiting can have serious effects. Nausea can leave you exhausted, anxious, and undernourished.
"It's important to control nausea," says Russell, who is also associate professor of medicine at the University of Southern California School of Medicine in Los Angeles. "If you don't, you might have to lower the doses of the chemotherapy drugs. That's something you want to avoid if at all possible." She says that uncontrolled nausea also makes people give up on their treatment.
Chronic vomiting can also have direct and serious consequences.
"Vomiting can throw off your balance of electrolytes," Syrjala tells WebMD. "Losing fluids can increase the toxicity of the chemotherapy. It can prevent you from going on with your treatment."
Chemotherapy Side Effects: Who's at Risk?
Who's at risk for chemotherapy side effects can depend on what drugs they take -- some are much more likely to cause symptoms than others.
For instance, without preventative treatment, chemotherapy drugs like Adriamycin (doxorubicin) and Platinol (cisplatin) have a greater than 90% chance of causing nausea and vomiting. But drugs like methotrexate or Navelbine (vinorelbine) pose less than a 10% risk.
While the type of medicine is the biggest factor, other things affect your chances of getting sick. Some risk factors are:
Talk to your doctor if you think you might be at higher risk of side effects. He or she might want you to start taking antinausea medicines before beginning chemotherapy.
Anticipatory Nausea -- Expecting to Get Sick
After starting treatment, about one out of three people in chemotherapy develop anticipatory, or conditioned, nausea. You may find that anything which reminds you of getting chemotherapy -- the smell of the doctor's office, the freeway exit that takes you to your clinic -- triggers queasiness. About one out of ten develop anticipatory vomiting.
"People are sometimes embarrassed of this," says Syrjala. "They think it's a sign of weakness to get sick before you actually get treatment." But that's not the case.
Syrjala says this is simply the body's natural response to anything that makes it sick. It happens for the same reason you might still have a strong aversion to a food that gave you food poisoningfood poisoning -- even if it happened decades ago. "Your body is just trying to protect you," she says.
While this connection can be broken after it's already been established, Syrjala says the best strategy is to prevent it. She recommends people at high risk of developing nausea take antinausea medicines before they start treatment. Changes in your behavior can help as well.
"One of the best things you can do is distract yourself," says Syrjala. For example, before and during chemotherapy, concentrate on something besides your treatment. An intense conversation, video games, or books-on-tape are all ways to do this.
New Antinausea Drugs
Chemotherapy drugs cause nausea in different ways. Some stimulate the nausea centers in the brain, says Russell, while others may stimulate parts of the esophagus, stomach, or intestines. Most antinausea drugs block the chemical stimulation of the nausea receptors.
Experts say that a treatment breakthrough came in the early 1990s, with the introduction of 5HT3 antagonists. "Those drugs were a huge step forward," says Russell. They include Anzemet (dolasetron), Kytril (granisetron), and Zofran (ondansetron.)
Russell says two new drugs are also helping. They are Emend (aprepitant) and Aloxi (palonosetron), a second generation 5HT3 antagonist. Experts use other types of drugs as well.
Improvements in medications have made a big difference for patients. "Fifteen years ago, the drugs we had to control nausea just weren't that effective," says Escalante. "Many people had to be hospitalized during chemotherapy. The nausea and vomiting was that bad."
But now, most chemotherapy is done on an outpatient basis. That's partly due to the success of new antiemetics, Escalante says.
Behavioral Therapy and Alternative Treatments
Some alternative therapies may also help control nausea and vomiting, especially in addition to medicines. They include:
"I have had a number of patients use acupuncture in addition to antiemetics," says Russell. "Some had a significant benefit." She urges people to talk to their doctors about new techniques if they feel their medicines aren't doing enough.
On the whole, Syrjala has no problem with alternative treatments like these, as long as the risks are low. But she and other experts warn against using herbs or supplements without talking to your doctor first.
"Herbs and supplements are real drugs," Syrjala says. "They can block the effects of your medication."
And Russell points out that no supplement has been proven to help. "Besides, if you're queasy, the last thing you want to do is pile more pills in your mouth," she says.
The Marijuana Debate
It's been long known that marijuana can soothe nausea. A synthetic version of the active ingredient in it, THC, is in the prescription drug, Marinol (dronabinol.)
But using marijuana raises some legal problems in most states, to say the least. Aside from those, Syrjala sees safety risks.
"You're ingesting something with unknown purity when your immune system is compromised," she says. "If you wind up inhaling a fungal agent, you won't have the immunity to fight it off."
But Russell says that marijuana can be an effective treatment.
"Obviously, I don't and can't prescribe marijuana," says Russell. "But it can relieve nausea." While she ideally doesn't want her patients smoking anything, she says that inhaled marijuana is a rapid and efficient drug delivery system.
"The most important thing is for people [to] get through their chemotherapy without nausea," Russell tells WebMD, "and they have to find the best way to do that."
Can Diet Help? Reducing Nausea With Food
There is no special chemotherapy diet. But experts say that foods that are spicy or strong smelling are more likely to cause nausea. While Syrjala says that bland diets are often easier to tolerate, everyone is different. You have to find the food choices that work for you.
"Ideally, I'd like people to eat a healthy diet during chemotherapy, so that they get enough vitamins and minerals," says Russell. "But the most important thing is to complete your chemotherapy on the prescribed dose. Any foods that get you through your treatment are probably OK."
However, one thing is crucial. You need to stay hydrated. Dehydration can interfere with your treatment and has other risks. "If you don't drink enough fluids, you can wind up in the emergency room," says Escalante.
You may find that eating smaller meals more often than you used to can prevent nausea, says Escalante. Although you should never force yourself to eat when you're nauseous, Russell says that it's important to eat regularly.
"Never come to get chemotherapy on an empty stomach," says Russell. "It just raises the risks that you're going to feel queasy. You won't know whether it was the drugs or just hunger."
Syrjala warns that turning to comforting foods when you're feeling ill can have an unexpected consequence: you might start to associate them with nausea.
"I tell people to avoid their absolute favorite foods, like chocolate, when they're susceptible to nausea," she says. "You don't want to lose the pleasure from those foods by connecting them with being sick."
Battling Chemotherapy Side Effects: Team Up With Your Doctor
If you need chemotherapy, don't be frightened of the side effects. Remember, nausea and vomiting aren't inevitable.
Before you begin treatment, be up front with your doctor. Ask if you're at high risk for nausea or vomiting. Find out if the drugs you'll use are likely to cause side effects. Plan ahead and you and your doctor can come up with a treatment plan to prevent problems, says Russell.
If you start treatment and find you have nausea or vomiting anyway, go right back to your doctor.
"If your medicines aren't working or not working well enough, talk to your health care provider," says Escalante. "There are always adjustments that he or she can make." You might try adding another drug or switching to a new one entirely.
"Just be honest with your doctor," Escalante tells WebMD. "Sometimes good communication is the key to controlling your nausea and feeling good again."
Published July 10, 2006.
SOURCES: American Cancer Society web site. "Nausea and Vomiting: Treatment Guidelines for Patients with Cancer." Carmen P. Escalante, MD, chair, department of general internal medicine; clinical medical director, Ambulatory Treatment Center, EVP & chief operating officer, University of Texas M. D. Anderson Cancer Center, Houston. National Cancer Institute web site, "Nausea and Vomiting PDQ: Health Professional Version." Christy Russell, MD, chair, American Cancer Society Breast Cancer Advisory Committee; associate professor of medicine, Keck School of Medicine, University of Southern California, Los Angeles. Karen Syrjala, PhD, psychologist; director of biobehavioral sciences, Fred Hutchinson Cancer Research Center, Seattle.