Peppermint is an herb that is a natural cross between two types of mint (water mint and spearmint) and grows throughout Europe and North America. Both peppermint leaves and the essential oil from peppermint have been used for health purposes. Peppermint is used as a dietary supplement for irritable bowel syndrome (IBS), other digestive problems, the common cold, headaches, and other conditions. Peppermint leaf is available in teas, capsules, and as a liquid extract. Peppermint oil is available as liquid solutions and in capsules, including enteric-coated capsules.
Peppermint oil should be taken as directed and is generally taken orally (by mouth) in moderate doses (only a few drops.) Excessive doses of peppermint oil can be toxic.
Possible side effects of peppermint oil include allergic reactions and heartburn. Excessive doses of peppermint oil can be toxic.
No harmful effects of peppermint leaf tea have been reported. However, the long-term safety of consuming large amounts of peppermint leaf is unknown.