Ginger, the underground stem, or rhizome, of the plant Zingiber officinale has been used as a medicine in Asian, Indian, and Arabic herbal traditions since ancient times. In China, for example, ginger has been used to aid digestion and treat stomach upset, diarrhea, and nausea for more than 2,000 years. Since ancient times, ginger has also been used to help treat arthritis, colic, diarrhea, and heart conditions. In addition to these medicinal uses, ginger continues to be valued around the world as an important cooking spice and is believed to help the common cold, flu-like symptoms, headaches, and even painful menstual periods. Native to Asia where its use as a culinary spice spans at least 4,400 years, ginger grows in fertile, moist, tropical soil.

Today, ginger root is widely used as a digestive aid for mild stomach upset and is commonly recommended by professional herbalists to help prevent or treat nausea and vomiting associated with motion sickness, pregnancy, and, sometimes, chemotherapy for cancer (although the latter has not been studied).

Motion Sickness
Several studies suggest that ginger may be more effective than placebo in reducing symptoms associated with motion sickness. In one trial of 80 novice sailors (prone to motion sickness), those who took powdered ginger experienced a significant reduction in vomiting and cold sweating compared to those who took placebo. Similar results were found in a study with healthy volunteers. While these results are promising, other studies suggest that ginger is not as effective as medications in reducing symptoms associated with motion sickness. In a small study of volunteers who were given ginger (fresh root and powder form), scopolamine (a medication commonly prescribed for motion sickness), or placebo, those receiving the medication experienced significantly fewer symptoms compared to those who received ginger. Given the safety of ginger, however, many people find it a welcome alternative to medications if it relieves their motion sickness.

Pregnancy Related Nausea and Vomiting
At least two studies have found that ginger is more effective than placebo in relieving nausea and vomiting associated with pregnancy. In a small study including 30 pregnant women with severe vomiting, those who ingested 1 gram of ginger every day for four days reported more relief from vomiting than those who received placebo. In a larger study including 70 pregnant women with nausea and vomiting, those who received a similar dosage of ginger felt less nauseous and experienced fewer vomiting episodes than those who received placebo. (Note: fresh ginger root is safe to use during pregnancy, but dried ginger root is not. See Precautions.)

Nausea and vomiting following surgery
Research has produced mixed results regarding the use of ginger in the treatment of nausea and vomiting following surgery. In two studies, 1 gram of ginger root before surgery reduced nausea as effectively as a leading medication. In one of these two studies, women who received ginger also required fewer nausea-relieving medications following surgery. Other studies, however, have failed to find the same positive effects. In fact, one study found that ginger may actually increase vomiting following surgery. For this reason, further studies are needed to determine whether ginger is safe and effective for the prevention and treatment of nausea and vomiting following surgery.

Inflammation
In addition to providing relief from nausea and vomiting, ginger extract has long been used in traditional medical practices to decrease inflammation. In fact, many herbalists today use ginger to help treat health problems associated with inflammation, such as arthritis, bronchitis, and ulcerative colitis. In a recent study of 261 people with osteoarthritis (OA) of the knee, those who received a ginger extract twice daily experienced less pain and required fewer pain-killing medications compared to those who received placebo. Although there have also been a few other studies of the benefit of ginger for arthritis, one recent trial found that the herb was no more effective than ibuprofen (a medication frequently used to treat OA) or placebo in reducing symptoms of OA.

Other
Although it is much too early to tell if this will benefit those with heart disease, a few preliminary studies suggest that ginger may lower cholesterol and prevent the blood from clotting. Each of these effects may protect the blood vessels from blockage and the damaging effects of blockage such as atherosclerosis, which can lead to a heart attack or stroke. Again, however, it is too early too know if these initial study results will ultimately prove helpful for people. More research would be helpful.

Ginger is a knotted, thick, beige underground stem (rhizome). The stem extends roughly 12 inches above ground with long, narrow, ribbed, green leaves, and white or yellowish-green flowers.

The important active components of the ginger root are thought to be volatile oils and pungent phenol compounds (such as gingerols and shogaols).

Ginger products are made from fresh or dried ginger root, or from steam distillation of the oil in the root. The herb is available in extracts, tinctures, capsules, and oils. Fresh ginger root can also be purchased and prepared as a tea. Ginger is also a common cooking spice and can be found in a variety of foods and drinks including ginger bread, ginger snaps, ginger sticks, and ginger ale.

Pediatric

Ginger should not be used by children under 2 years of age.

Ginger may be used by children over 2 years of age to treat nausea, digestive cramping, and headaches. Adjust the recommended adult dose to account for the child's weight. Most herbal dosages for adults are calculated on the basis of a 150 lb (70 kg) adult. Therefore, if the child weighs 50 lb (20 to 25 kg), the appropriate dose of ginger for this child would be 1/3 of the adult dosage.

Adult

In general, ginger intake should not exceed 2 to 4 g per day (this includes the ginger obtained through diet such as from ginger ale, ginger snaps, and ginger bread).

• For nausea, gas, or indigestion: 2 to 4 grams of fresh root daily (0.25 to 1.0 g of powdered root) or 1.5 to 3.0 mL (30 to 90 drops) tincture daily. To prevent vomiting, take 1 gram of powdered ginger (1/2 tsp) or its equivalent every four hours as needed, or 2 ginger capsules (1 gram) three times daily. You may also chew a ¼ oz piece of fresh ginger.
• To relieve arthritis pain: Take fresh ginger juice, extract, or tea, 2 to 4 grams daily; rub ginger oil into painful joint; or place fresh root in a warm poultice or compress and apply to painful areas.
• For cold and flu symptoms, sore throat, headache and menstrual cramps: Steep 2 tbsp of freshly shredded ginger in boiled water, two to three times daily, or place a drop of ginger oil or a few slices of fresh rhizome in steaming water and inhale.

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

The American Herbal Products Association (AHPA) gives fresh ginger root a class 1 safety rating, indicating that it is a safe herb with a wide dosage range. Side effects associated with ginger are rare, but if taken in excessive doses the herb may cause mild heartburn. The AHPA gives dried ginger root a class 2b rating, indicating that it should not be used during pregnancy.

People with gallstones should consult a physician before taking ginger.

If you are currently being treated with any of the following medications, you should not use ginger without first talking to your healthcare provider.

Blood-thinning medications
Although ginger may interfere with blood clotting, there have been no scientific or case reports of interactions between ginger and blood-thinning medications. However, people taking these medications with ginger should be monitored closely by a healthcare practitioner for risk of bleeding.

Cyclophosphamide
Ginger may reduce the toxic side effects of cyclophosphamide (a medication used to treat a variety of cancers). More research is needed in this area.

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