When applied topically, it acts as a counter-irritant and analgesic with the ability to reduce pain and improve blood flow to the affected area. This may explain its usefulness in treating tension headaches. Topical peppermint oil alone reduced pain as well. For headaches, a combination of peppermint oil and eucalyptus oil diluted with base oil can be applied to the temples at the onset of the headache and every hour after that or until symptom relief is noted. Peppermint tea is generally considered safe for regular consumption.
Peppermint oil can cause burning and gastrointestinal upset in some people.
It should be avoided by persons with chronic heartburn , severe liver damage, inflammation of the gallbladder, or obstruction of bile ducts. 17 People with gallstones should consult a physician before using peppermint leaf or peppermint oil. Some persons using enteric-coated peppermint capsules may experience a burning sensation in the rectum. Rare allergic reactions have been reported with topical use of peppermint oil. Certain medications may interact with peppermint.