Ginger is a knotted, thick, beige underground stem, called a rhizome. The stem sticks up about 12 inches above ground with long, narrow, ribbed, green leaves, and white or yellowish-green flowers.

 Researchers think the active components of the ginger root are volatile oils and pungent phenol compounds, such as gingerols and shogaols.

Today, health care professionals may recommend ginger to help prevent or treat nausea and vomiting from motion sickness, pregnancy, and cancer chemotherapy. It is also used to treat mild stomach upset, to reduce pain of osteoarthritis, and may even be used in heart disease.

Motion sickness

Several studies, but not all, suggest that ginger may work better than placebo in reducing some symptoms of motion sickness. In one trial of 80 new sailors who were prone to motion sickness, those who took powdered ginger had less vomiting and cold sweats compared to those who took placebo. Ginger did not reduce their nausea, however. A study with healthy volunteers found the same thing.

However, other studies found that ginger does not work as well as medications for motion sickness. In one small study, people were given either fresh root or powdered ginger, scopolamine, a medication commonly prescribed for motion sickness, or a placebo. Those who took scopolamine had fewer symptoms than those who took ginger. Conventional prescription and over-the-counter medicines for nausea may also have side effects that ginger does not, such as dry mouth and drowsiness.

Pregnancy-related nausea and vomiting

Human studies suggest that 1g daily of ginger may reduce nausea and vomiting in pregnant women when used for short periods (no longer than 4 days). Several studies have found that ginger is better than placebo in relieving morning sickness.

In a small study of 30 pregnant women with severe vomiting, those who took 1 gram of ginger every day for 4 days reported more relief from vomiting than those who took placebo. In a larger study of 70 pregnant women with nausea and vomiting, those who got a similar dose of ginger felt less nauseous and did not vomit as much as those who got placebo. Pregnant women should ask their doctors before taking ginger and not take more than 1g per day.

Chemotherapy nausea

A few studies suggest that ginger reduces the severity and duration of nausea, but not vomiting, during chemotherapy. However, one of the studies used ginger combined with another anti-nausea drug. So it is hard to say whether ginger had any effect. More studies are needed.

Nausea and vomiting after surgery

Research is mixed as to whether ginger can help reduce nausea and vomiting following surgery. Two studies found that 1g of ginger root before surgery reduced nausea as well as a leading medication. In one of these studies, women who took ginger also needed fewer medications for nausea after surgery. But other studies have found that ginger did not help reduce nausea. In fact, one study found that ginger may actually increase vomiting following surgery. More research is needed.

Osteoarthritis

Traditional medicine has used ginger for centuries to reduce inflammation. And there is some evidence that ginger may help reduce pain from osteoarthritis (OA). In a study of 261 people with OA of the knee, those who took a ginger extract twice daily had less pain and needed fewer pain-killing medications than those who received placebo. Another study found that ginger was no better than ibuprofen (Motrin, Advil) or placebo in reducing symptoms of OA. It may take several weeks for ginger to work.

Other uses

Preliminary studies suggest that ginger may lower cholesterol and help prevent blood from clotting. That can help treat heart disease where blood vessels can become blocked and lead to heart attack or stroke. Other studies suggest that ginger may help improve blood sugar control among people with type 2 diabetes. More research is needed to determine whether ginger is safe or effective for heart disease and diabetes.

Ginger products are made from fresh or dried ginger root, or from steam distillation of the oil in the root. You can find ginger extracts, tinctures, capsules, and oils. You can also buy fresh ginger root and make a tea. Ginger is 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

DO NOT give ginger to children under 2.

Children over 2 may take ginger to treat nausea, stomach cramping, and headaches. Ask your doctor to find the right dose.

Adult

In general, DO NOT take more than 4 g of ginger per day, including food sources. Pregnant women should not take more than 1 g per day.

• For nausea, gas, or indigestion:Some studies have used 1 g of ginger daily, in divided doses. Ask your doctor to help you find the right dose for you.
• For pregnancy-induced vomiting:Some studies have used 650 mg to 1 g per day. DO NOT take ginger without talking to your doctor first.
• For arthritis pain: One study used 250 mg, 4 times daily.

The use of herbs is a time-honored approach to strengthening the body and treating disease. However, herbs can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken under the supervision of a health care provider, qualified in the field of botanical medicine.

It is rare to have side effects from ginger. In high doses it may cause mild heartburn, diarrhea, and irritation of the mouth. You may be able to avoid some of the mild stomach side effects, such as belching, heartburn, or stomach upset, by taking ginger supplements in capsules or taking ginger with meals.

People with gallstones should talk to their doctors before taking ginger. Be sure to tell your doctor if you are taking ginger before having surgery or being placed under anesthesia.

Pregnant or breastfeeding women, people with heart conditions, and people with diabetes should not take ginger without talking to their doctors.

DO NOT take ginger if you have a bleeding disorder or if you are taking blood-thinning medications, including aspirin.

Ginger may interact with prescription and over-the-counter medicines. If you take any of the following medicines, you should not use ginger without talking to your health care provider first.

Blood-thinning medications: Ginger may increase the risk of bleeding. Talk to your doctor before taking ginger if you take blood thinners, such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin.

Diabetes medications: Ginger may lower blood sugar. That can raise the risk of developing hypoglycemia or low blood sugar.

High blood pressure medications:Ginger may lower blood pressure, raising the risk of low blood pressure or irregular heartbeat.

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