Fennel for Nausea

Anything from burgers to bacteria can irritate the nerve endings in your stomach and other parts of your body to cause nausea. Triggers include pain, emotional stress, motion sickness, food poisoning and hormonal shifts during early pregnancy. While few scientific studies confirm its efficacy, herbalists suggest that the herb fennel may help ease that queasy sensation in your stomach. Herbal therapies, however, do not take the place of professional medical advice, so consult your physician if nausea persists.

Fennel Facts

Indigenous to the Mediterranean region, the fennel plant now grows in temperate zones around the world. Fennel, or Foeniculum vulgare, is an aromatic perennial that reaches heights of 5 feet and bears feathery leaves and umbrella-like clusters of yellow flowers. Its small, ovate seeds, the source of the plant's medicinal properties, contain the key ingredients anethole, fenchone and estragole. Herbalists use fennel seeds to treat a variety of digestive problems, including bloating, stomach pain, gas and nausea.

Potential Benefits

Fennel seeds have antispasmodic, antimicrobial, pain-relieving and fever-reducing properties that help to treat nausea due to food poisoning, colic, indigestion and motion sickness, claims Phyllis A. Balch, certified nutritional consultant and author of the book "Prescription for Herbal Healing." According to Balch, fennel helps to expel gas and kills certain types of bacteria. Fennel also appears to produce gastrointestinal motility effects, meaning it promotes digestion and helps to prevent stomach spasms that can trigger the nausea-vomiting mechanism. Limited clinical studies confirm these claims, however.

Evidence

Even among herbalists, fennel oil's benefits remain contradictory. While Charles W. Kane, author of the book "Herbal Medicine Trends and Traditions," agrees that fennel may help relieve gas and nausea associated with indigestion, he adds that other herbs, such as ginger or spearmint, better treat pregnancy-related nausea. A Russian clinical trial published in the July-August 2003 issue of "Alternative Therapies in Health and Medicine" found that fennel oil eliminated infantile colic in 65 percent of participants. While research indicates that fennel seed oil seems to inhibit intestinal spasms and stimulate motility of your small intestine, no clinical trials specifically target fennel's effects on nausea. Furthermore, "World Journal of Gastroenterology" published a June 14, 2010 article that indicated that certain spices, including fennel, may actually increase stomach acids and induce damaging effects on the gastric mucosal lining.

Considerations

Generally recognized as safe, pure essential oil extracted from fennel seeds can be toxic. Pure fennel seed oil can cause burning inflammation of the lower intestinal tract, skin irritations, respiratory problems and seizures, according to Steven Foster, author of the book "National Geographic Desk Reference to Nature's Medicine." Large doses of undiluted fennel oil can also increase estrogen levels in females, so pregnant women and others with estrogen-sensitive disorders should avoid the herb. Additionally, fennel may interfere with certain medications, and has contradictory effects on the liver.