Acupuncture as an add-on to anti-emetic medication can reduce risk for vomiting in the 24 hours after chemotherapy administration, according to a meta-analysis published in Issue 2 (2006) of The Cochrane Database of Systematic Reviews.

Among varying forms of acupuncture, only electroacupuncture, in which a small electrical current is passed through the inserted needle, reduced the incidence of vomiting directly after chemotherapy. However, the significance of acupuncture technique is less clear because the electroacupuncture studies were the only ones that did not use the most recent generation of anti-emetic medication.

Information pooled from nine studies found that 22 percent of patients (155 of 714 patients) who received acupuncture had acute vomiting the first day after chemotherapy compared with 33 percent (154 of 500 patients) of those who did not receive acupuncture.

Jeanette Ezzo, PhD, and colleagues also evaluated acupressure, in which acupuncture points are stimulated by gentle pressure from the fingers or a studded wristband, as well as mild electrical stimulation at the acupuncture points from electrodes placed on the skin.

Acupressure was the only technique among all acupuncture treatments reviewed to reduce the likelihood of nausea the day after chemotherapy, although it did not affect vomiting.

“If our finding is correct, then acupressure offers a no-cost, convenient, self-administered intervention for chemotherapy patients to reduce acute nausea,” Ezzo said, while acknowledging that the placebo effects of all nausea treatments “can be substantial.”

Electrical stimulation did not affect either nausea or vomiting. None of the acupuncture studies had enough data to determine whether any anti-nausea or anti-vomiting effects lasted beyond the first 24 hours after chemotherapy.

Ezzo and colleagues were unsure why electroacupuncture reduced vomiting while needles-only acupuncture did not. Differences existed in how many acupuncture points were stimulated and how long the stimulation lasted among the largest studies, which may have affected the results, according to the Cochrane reviewers.

Because all the acupuncture studies in the Cochrane review also used anti-vomiting medication, the research doesn’t offer a clear answer as to whether acupuncture would be helpful for patients who get no relief from the drugs, Ezzo said.

“The clinician can relay what is known and leave it to the patient to decide,” she said.