The antipsychotic agent olanzapine may be helpful in reducing nausea and vomiting caused by advanced cancer, according to results of a study by Loprinzi et al published recently in JAMA Oncology. “There was a dramatic reduction [in nausea and vomiting] within 24 hours in the people who received olanzapine, and it lasted for the entire week that patients were formally studied,” said Charles Loprinzi, MD, one of the study’s investigators. Dr. Loprinzi is Professor of Oncology at the Mayo Clinic in Rochester, Minnesota. The study was funded by the National Cancer Institute (NCI).
Charles Loprinzi, MD
A total of 30 people with different types of advanced cancer and chronic nausea due to the cancer itself, bowel obstruction, or opioid medications, were randomly assigned to olanzapine or placebo for 1 week. None had received chemotherapy or radiation therapy in the 2 weeks prior to enrolling, or antipsychotic medications in the 30 days prior to enrolling. The study was double-blinded.
Before treatment began, each patient rated the intensity of their nausea, fatigue, sedation, appetite, and pain. They scored each symptom on a scale of 0 to 10, with 10 representing the highest intensity. After treatment started, they repeated the evaluation of their symptoms daily for a week.
For those in the placebo group, the median nausea score didn’t change after 1 day or after 1 week of treatment. But for those in the olanzapine group, the median nausea score dropped to 2 after the first day of treatment and to 1 after a week.
Before beginning treatment, patients in both groups reported vomiting two to three times a day. During the treatment, patients in the placebo group continued to vomit at the same rate, while those in the olanzapine group reported no vomiting.
It was surprising to see such a large benefit for every patient who took olanzapine, Dr. Loprinzi said, noting the varied causes for nausea and vomiting.
Diane St. Germain, RN, MS
“The results are quite impressive,” said Diane St. Germain, RN, MS, of NCI’s Division of Cancer Prevention, who wasn’t involved in the study. Although the study was small, it shows that olanzapine has efficacy and “definitely indicates that a larger study is needed,” she added.
Before treatment began, the median nausea score for all participants was 9 out of 10. These “patients had really significant nausea and vomiting. These were patients who were clearly struggling,” St. Germain said.
The study findings also show that olanzapine caused very few side effects.
Olanzapine is mainly used to treat schizophrenia, bipolar disorder, and depression. It is also used off-label to prevent nausea and vomiting caused by chemotherapy.
Dr. Loprinzi and his colleagues are designing a trial that will further explore longer-term effects of olanzapine.
Also, olanzapine is available as a generic drug and is relatively inexpensive, Dr. Loprinzi said.