(USA TODAY) -- New research highlights drugs that make cancer therapy easier, but it also underscores the difficulties patients may encounter after treatment.

A commonly used schizophrenia drug, Zyprexa, reduced the number of patients suffering from chemotherapy-related nausea and vomiting by more than half in a study of 80 patients presented before the annual meeting of the American Society of Clinical Oncology June 1-4 in Chicago.

The study focused on patients who were getting a heavy, triple-drug chemo combination and were not helped by anti-nausea medications.

In the new study, led by Rudolph Navari of the Indiana University School of Medicine-South Bend, 68% of patients randomly assigned to a standard drug, Reglan (metoclopramide), ended up vomiting, vs. 29% of those on Zyprexa, sold generically as olanzapine.

About 76% of those taking Reglan still had nausea, vs. 33% of those on Zyprexa, the study says. Patients took the drugs orally for three days. Though taking Zyprexa long-term can cause side effects such as weight gain, doctors didn't note any major problems in patients on the short-term regimen. .

"This is a huge advance," says Sandra Swain, president-elect of the clinical oncology society. Nausea and vomiting are serious problems for many cancer patients, she says, and some even stop taking their medications. For others, side effects disrupt their lives, making it hard to work or care for their families.

Nausea and vomiting from chemotherapy is not like that from a stomach virus, says Andrew Putnam, an assistant professor of oncology and medicine at Georgetown Lombardi Comprehensive Cancer Center. Instead of upsetting the digestive tract, chemo activates the brain's "vomiting center," Putnam says. That's why an antipsychotic drug such as Zyprexa, which works on the brain, is able to help.

Breast cancer survivor Renee Nicholas, 37, says nausea from her therapy was debilitating. She says she tried many anti-nausea drugs; "I even tried acupuncture once or twice a week."

Another study, by Larissa Nekhlyudov of Harvard Medical School, finds that many primary care doctors, and even some oncologists, aren't well-informed about problems faced by cancer survivors. Though cancer patients are typically seen by specialists during treatments, they often return to generalists when they finish therapy, says Michael Link, the society's current president. But treatments can be highly toxic, with side effects to heart, bones and even the brain. Some therapies can push patients into early menopause, and others can cause new cancers.

The study shows why it's important for every patient to get a treatment summary and survivorship plan after active therapy ends, Link says. Findings also reinforce the need to expand use of electronic medical records to make sharing such information easier.

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