context: Doctors have used chemotherapy (chemo) to treat cancer since the 1950s. The advantage to these drugs is they kill cancer cells throughout your body. One downside is the side effects they can cause -- including upset stomach. In the past, people who got chemo had to live with the intense nausea and vomiting. That's no longer true. Today, doctors have many drugs to stop -- and even prevent -- them. Your body sees the medicine as foreign. It sets off warning signals in your brain and digestive system. This flips the on switch in a part of your brain called the vomiting center. It puts out chemicals that make you queasy. Chemo can harm your digestive tract, too, which could also lead to nausea. Chemo can cause three different types of nausea and vomiting: Acute starts within a few hours of your treatment. Delayed won't kick in until 24 hours after treatment. It can last a few days Anticipatory starts before you get chemo, because you expect to feel sick. Constant vomiting can take a toll. It can leave you weak, dry your body out, and steal nutrients it needs. You might also get an electrolyte imbalance, which means you don't have enough of things like sodium and potassium that make your systems run. If you feel very sick, you might have to lower your chemotherapy dose or stop the treatment entirely. Some types of chemo are more likely than others to make you sick. It happens more often with the drugs cisplatin ( Platinol) and doxorubicin ( Adriamycin). You're also more likely to have these problems if you: Get several chemotherapy treatments close together Take a high dose Get the drug through a vein instead of by mouth Are female Are younger than 50 Tend to get motion sickness Your doctor can give you medicine before your treatment to prevent sickness. You might take one of these medicines to block signals to the part of your brain that makes you ill: Aprepitant ( Cinvanti, Emend) Dolasetron ( Anzemet) Fosnetupitant/palonosetron ( Akynzeo) Granisetron ( Kytril, Sustol, Sancuso) Ondansetron ( Zofran, Zuplenz) Palonosetron ( Aloxi) Rolapitant ( Varubi) You get these medicines through a vein ( IV) or by mouth. Akynzeo and Aloxi keep working for a few days, so they can prevent delayed nausea and vomiting. A few other types of drugs can also help: Anti-anxiety drugs: alprazolam ( Niravam, Xanax), diazepam ( Valium), and lorazepam ( Ativan) Cannabinoids: abilone ( Cesamet)dronabinol ( Marinol, Syndros) Corticosteroids: dexamethasone ( Decadron, Hexadrol)methylprednisolone ( Medrol) Dopamine antagonists: metoclopramide ( Reglan)prochlorperazine Motion sickness medicines: scopolamine patch ( Transderm Scop) Drugs aren't the only option. You might try a complementary therapy -- a type of treatment that's outside traditional medicine but can be used along with it to ease your symptoms. Acupuncture is a form of Chinese traditional medicine that uses fine needles to stimulate various pressure points around your body. The idea is to restore your natural energy flow. The practitioner may even add an electric current to boost the effect. The point that's often used to treat nausea is called P6. It's located on the underside of the wrist, a couple of inches below your hand. Side effects are usually mild, including pain and minor bleeding where the needles go in. Acupressure is similar acupuncture, but uses firm pressure instead of needles. Biofeedback teaches you how to control body functions that usually happen automatically. You can learn how to slow your heart rate or breathing to calm you down. Hypnosis gets you into a state where you're focused and open to suggestion. You can go to a hypnotist or use self-hypnosis to bring about changes in behavior. Taking your mind off your treatment can help you manage the sickness. Try these techniques to relax or distract yourself before chemotherapy: Guided imagery. Use your imagination to picture yourself in a calming scene -- like a tranquil village by a lake. Imagine your stress drifting away from you like a boat sailing off on the current. Distraction. Listen to music, read a book, or watch a funny movie to take your mind off the treatment ahead. Progressive muscle relaxation. Start at your feet. Tense and then relax each muscle group in your body. By the time you reach your head, you should feel much calmer. You can also make a few changes to what you eat and your daily routine to prevent and relieve nausea: Avoid any foods that make you feel sick. Common culprits include fatty, fried, and strong-smelling foods. Eat several small meals throughout the day instead of three big meals. Have a snack before your chemo treatment. Don't cook when you don't feel well. The smell of warming food can make nausea worse. Eat cold foods if the smell of hot food bothers you. Drink extra water and other fluids so you don't get dehydrated. Eat candied ginger or drink flat ginger ale or ginger tea to settle your stomach.