Nausea and vomiting are still an obvious problem in patients receiving chemotherapy. On conditioning with more than 24 h of chemotherapy, patients are at risk for CINV throughout the entire treatment period. Aromatherapy is the inhaled use of essential oils for therapeutic or medical purposes. Ginger (Zingiber officinale), spearmint (M. spicata), and peppermint (M. × piperita) are recommended for their antiemetic and antispasmodic effects on the gastric lining and colon. Several studies show the efficacy of peppermint in reducing postoperative nausea and vomiting [6], chemotherapy-induced nausea [7], and colonic spasms during colonoscopy [89] and after colostomy surgery [10].

Exposure to ionising radiation induces nausea and vomiting, such as in radiation accidents. Hence, plants with antiemetic activity (e.g. Centella asiatica, M. × piperita, and Zingiber officinale) have been evaluated for their ability to provide radiation protection [1114]. Nevertheless, M. × piperita and M. spicata essential oils have not been fully analysed in populations.

In this study, we used spearmint and peppermint capsules (containing two drops of each essential oil every four h, filled with sugar, and administered 30 minutes before they received their chemotherapy treatment, again four h after first capsule and finally four h later in home) for all patients, independent of their age or weight. Furthermore, no significant side effects were found when increasing the dose.

Although it was not our aim to compare spearmint and peppermint, we found no difference between these two herbs in the control of vomiting in the first 24 h (p > 0.05).

Based on our results, we have concluded that the essential oils of spearmint and peppermint are less expensive, and a safe and effective therapeutic option for the treatment of chemotherapy-induced nausea and emesis in patients.