Ginger root relieves nausea and emesis and may prevent or reduce the symptoms of motion sickness and seasickness. While nausea is currently the main indication for use, inhibition of cyclooxygenase and lipoxygenase inflammatory pathways and related prostaglandin synthetase and platelet aggregation support the use of ginger in colds, sore throats, flus, headaches, and some types of arthritis and muscular pain.

As a culinary spice, ginger was known for centuries to reduce flatulence, bloating, and indigestion, and to stimulate the appetite. It was highly sought after by Europeans, who traded with China and India during the sixteenth and seventeenth centuries and used it fresh, powdered, or crystallized in cooking. In 1884, England is said to have imported more than 5 million pounds of ginger.

Native to Asia where its use as a culinary spice spans at least 4,400 years, ginger grows in fertile, moist, tropical soil. It was transported as far west as Jamaica, where it became an export crop as early as 1547. Explorers and settlers brought it to southern Florida and further west to Mexico.

Ginger can be grown at home by planting rhizomes in soils of mixed loam, sand, peat moss, and compost in bright sun with plenty of water. Within a year, gnarled, branched rhizome spread throughout the soil, bearing numerous tubers.

White, yellow, or greenish-yellow flowers, which may have a purplish tint at the edges, form at cone-shaped, three-inch spikes, off erect 6- to 12-inch stalks (cultivated ginger rarely flowers). Above ground leaves are dark green, narrow, lanceolate or linear-lanceolate, with a noticeable rib. The rhizome is light beige, aromatic, and has a sharp, spicy flavor.

• Roots (rhizome)

Volatile oil containing sesquiterpenes (zingiberene, bisabolene); oleoresin with pungent principles (gingerols, shogaols)

Fresh or dried rhizome prepared as aqueous, aqueous-alcohol, glycerite, or dried powder liquid extracts including tinctures and syrups; oil; rhizome tea; dried, powdered tablets, capsules; crystallized ginger

Traditional herbal actions: carminative, diaphoretic, antispasmodic, antiemetic, cholagogue, circulatory stimulant, peripheral vasodilator, expectorant, antiseptic, topical rubifacient

Conditions: intestinal colic, flatulence, indigestion, headache, sore throat, arthritis, common cold, flu, delayed menstruation, pelvic congestion, menstrual cramps

Clinical applications: motion sickness, nausea, vomiting, indigestion, flatulence, common cold, flu, dysmenorrhea; also used topically for arthritis, sore joints, and muscle sprains.

Ginger root increases gastric motility, stimulates bile secretion, and is carminative and antiemetic. It promotes bile flow and reduces inflammation through prostaglandin inhibition.

In studies in animals, ginger or its oleoresin or volatile oil components are hypoglycemic, hypo- and hypertensive, anthelmintic (Anisakis larvae) in vitro, and positively inotropic. Ginger inhibits cholesterol absorption after time, increases bile flow, and inhibits hydrochloric acid/ethanol-induced gastric lesions. It also inhibits prostaglandin biosynthesis and platelet aggregation in vitro.

In humans, ginger relieves motion sickness comparably to dimenhydrinate (Dramamine), most likely through actions within the gastrointestinal tract and not on the central nervous system, at doses of up to 2 g every four hours or as needed. Its superiority to dimenhydrinate remains equivocal. Currently, at least one formulation awaits FDA approval for over-the-counter status for treating nausea and motion sickness.

High doses of ginger (10 to 20 g of fresh ginger per day, or 500 mg of dried ginger four times a day) were found to significantly reduce migraine intensity and rheumatoid arthritis pain, respectively. Rheumatoid arthritis patients receiving either 5 to 50 g of fresh ginger or 0.1 to 1.0 g of powdered root experienced significant reductions in joint pain and an increase in mobility. These effects may be due to cyclooxygenase and lipoxygenase pathway inhibition.

Daily dose:

• 2 to 4 g daily of fresh root (0.25 to 1.0 g of powdered root)

To relieve nausea, flatulence, or indigestion:

• 2 to 4 g daily of fresh root (0.25 to 1.0 g of powdered root) or 1.5 to 3.0 ml tincture daily, relative to the strength and processing of the tincture

To prevent emesis:

• 1 g ginger (½ tsp.) every 4 hours as needed
• 2 ginger capsules (1 g) tid
• ¼ oz. piece of fresh ginger, chewed

To relieve cold symptoms, fever associated with flu, sore throat, menstrual cramps, headache:

• Steep 2 tbsp. of freshly shredded ginger in boiled water, bid to tid.
• Place a drop of ginger oil or a few slices of fresh rhizome in steaming water and inhale.

To relieve arthritis:

• Fresh ginger juice, extract, or tea, 2 to 4 g daily
• Use oil or fresh root in a warm poultice or compress and apply to painful areas. Place a drop of ginger oil in massage oil and rub into painful joints and muscles.

American Herbal Products Association (AHPA) safety rating: fresh root, class 1 (safe with appropriate use); dried root, class 2b (not to be used during pregnancy). May cause mild heartburn.

Because ginger increases bile flow, gallstones contraindicate use.

The use of ginger to control morning sickness during pregnancy is controversial. Ginger obtained through food is not considered risky during pregnancy. Doses of 1 g dried ginger root to relieve morning sickness has not resulted in any reports of miscarriage or toxicity to either the fetus or the mother. The AHPA does not advise dried root during pregnancy.

Two Japanese studies showed in vitro mutagenicity for one of the pungent principles of ginger. Subsequent studies showed that risk to humans is diminished significantly by antimutagenic properties of other ginger constituents. Some Chinese sources claim that 20 to 28 g of ginger will cause miscarriage, presumably due to its effects on uterine smooth muscle tissue. Pregnant women are advised not to ingest more than normal dietary levels of ginger, such as those found in ginger ale, cookies, breads, and main dishes.

No clinically significant interactions between ginger and conventional medications are known to have been reported in the literature to date, including the German Commission E monograph (Blumenthal 1998). Although ginger inhibits thromboxane synthetase, interactions with anticoagulants have not been documented. Patients taking ginger while on anticoagulant therapy should be monitored closely (Miller 1998).

Ginger is a GRAS (generally recognized as safe) food additive in the United States and the FDA categorizes it as a dietary supplement. Recently published United States Pharmacopeia (USP) Information Monographs do not recommend therapeutic use of ginger, citing insufficient scientific evidence; OTC approval by the FDA has not yet been granted. In England, ginger is licensed through the General Sale List, and in Germany it is approved as a nonprescription drug for dyspepsia and motion sickness by the Commission E.

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