Herb library · Herb · Mentha x piperita
Peppermint
A mint whose leaves make tea and whose concentrated oil comes in capsules. The oil has a small research base, mostly for irritable bowel syndrome; the leaf has very little.
Traditional use
A natural cross between water mint and spearmint, used for digestive complaints since ancient Greece, Rome, and Egypt. Today it is promoted for irritable bowel syndrome, indigestion, headaches, muscle tension, and nausea.
What studies show
- Limited
Irritable bowel syndrome: a small amount of research suggests enteric-coated peppermint oil capsules may improve IBS symptoms in adults; a 2022 review of 10 studies found it better than placebo, with more mild side effects, and a 2021 gastroenterology guideline recommended it.
- Limited
Nausea during chemotherapy: a small amount of research suggests peppermint extract by mouth, or inhaled peppermint oil, may reduce nausea and vomiting.
- Insufficient
Indigestion: no evidence shows peppermint oil alone helps, and it may worsen indigestion for some; a few studies of specific blends with caraway oil or peppermint leaf suggested those may help.
- Limited
Tension headache and skin uses: a limited amount of evidence suggests peppermint oil on the skin might ease tension headaches, bed sores, and cracked nipples while breastfeeding.
- Insufficient
Peppermint leaf and tea: very little research exists, and NCCIH says there is not enough evidence to determine whether the leaf is useful for any condition.
Be careful of
Cautions
- NotePeppermint oil appears safe by mouth or on the skin in usual doses. It can cause heartburn (less with enteric coating), nausea, abdominal pain, dry mouth, or skin irritation. Peppermint tea appears safe; the long-term safety of large amounts of leaf is unknown.
- AllergyRarely, peppermint oil causes allergic reactions.
- ConditionNever apply peppermint oil to an infant's or young child's face or let them inhale it; the menthol may affect their breathing. On nipples, apply after feeding and wipe off before the next feed.
- PregnancyFood amounts are likely safe in pregnancy and while breastfeeding; little is known about medicinal amounts.
- Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, are pregnant or breastfeeding, or have a medical condition.
From the old books
What herbals and dispensaries of the past printed. History, in their words.
“The infusion may be drank freely; but the most usual form of administration is the essence, made by dissolving 1 fluid drachm of the oil in 1 fluid ounce of alcohol.”
Sources
- Peppermint Oil: Usefulness and Safety (opens in a new tab) · NCCIH · read September 15, 2026
Reviewed September 15, 2026.