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Zingiber officinale

Synonyms

No documentation.

Vernacular Name

Nagara, ardhrakam, adrak, ginger, ada, palu, inguru, shoga, chiang, inguere, gingembre, zanjabil urratab, zanjabil ee-e-tar, sge u-sger, khenseing, gnji. [1]

Description

Z. officinale, a perennial, grows up to 1m and yields small oblong leaves, but is mostly grown for its bulbous rhizome which is used as a spice, condiment or for its medicinal value. [2]

Origin / Habitat

Nagara is a widely cultivated reed-like herb that is most known for its pungent rhizome. Originating in China, Nagara is now mainly cultivated in India, where it is a very useful plant in Ayurvedic medicine.

Chemical Constituents

1-2% of rhizome contains yellow oil which is where the distinctive smell and taste come from. The oil is comprised of borneol, camphene, cineol, gingerol, phellandrene, and zingiberine. [1]

Plant Part Used

Rhizome. [3]

The rhizome is scraped and dried, then powdered. In some cases the green rhizome may be used.

Traditional Use

Nagara is primarily used in Ayurveda as a digestive aide, often used to combat dyspepsia, flatulence and colic. In addition to being used as an aid in digestion, Ayurvedic medicine finds use for Nagara in colds and fever as well as inflammation and rheumatism. [3] Small pieces of the dried rhizome are traditionally used to increase the flow of saliva in easing the discomfort of sore throat, raspy cough, laryngitis and general oral discomforts. It is also combined with rock salt and taken before meals to cleanse the tongue and increase the appetite. [4] Of interest is a report that a dried preparation of Nagara had anti-rhinoviral activity in vitro. [5] Nagara also has antibacterial properties and has been used for this purpose in traditional therapies. [6][7] Nagara is classified as having a Katu (pungent) rasa (taste). [1] Nagara pacifies the kapha and pitta doshas. [4] 

Dosage

1-2g Powder, 7-20ml Infusion for traditional use. [1]

Pharmacology

Pre-clinical

Two-hundred and forty seven patients completed a randomized, double-blind, placebo-controlled, multicenter, parallel-group study lasting 6-weeks evaluating the safety and efficacy of 2 Nagara species (Zingiber officinale and Alpinia galanga) in osteoarthritis (OA) of the knee. The Nagara extract group had greater response in the primary endpoint of reduced knee pain upon standing as well as all the secondary endpoints evaluated. Less rescue medication (acetaminophen) was used by the Nagara group. More gastrointestinal adverse effects, most of them mild were experienced by the Nagara group. It is important to note that the change in the quality of life was equal between the Nagara and placebo group. [8] Another study found no significant advantage of using Nagara root over conventional anti-inflammatory agents such as ibuprofen. [9] 

Clinical

Nagara may also be of value in the treatment of hyperemesis gravidarum, a condition in morning sickness where severe dehydration and electrolyte disturbances may occur through excessive vomiting. [10] In addition, two double-blind, controlled clinical studies reported that the use of Nagara for treatment of nausea in pregnancy was found to decrease the number of events as well as lessening the severity of nausea. [11][12] A randomized, controlled equivalence trial found that women using Nagara in early pregnancy will reduce their symptoms. [13] The effectiveness of Nagara root pre-surgically as an antiemetic agent was comparable with metoclopramide in a double-blind, placebo controlled study. [14] Nagara root preparations may be useful in controlling nausea and vomiting after surgery with general anesthesia and in outpatient surgery. [15][16] However, there has been a report of dried Nagara root having no value in decreasing postoperative nausea, but product quality and lack of standardization may have contributed to this negative finding. [17] Several studies have been published which support Nagara’s antiemetic activity compared to drug or placebo therapy. [18][19][20][21] 

Shogaol is thought to give Nagara its antiemetic effect, and some authors report that this effect may be due to in part to Nagara’s increase in gastric emptying and its thromboxane synthetase activity. [22][23][24] A recent analysis of clinical studies on Nagara’s effectiveness in decreasing nausea reported that the studies collectively favored Nagara over placebo. [25] Nagara has also been reported to decrease the nausea associated with certain chemotherapy and radiation treatments. [26] 

Whether or not Nagara works on the CNS or locally in the gut is debated, but research has reported both central and peripheral involvment. [27] A small human study did report however that a Nagara root powder preparation had no effect on gastric emptying. [28] Nagara’s structural phenols are similar to aspirin and may have an effect on prostaglandins, PGE2 and PGF2, as well as thromboxane, leading to its use as a platelet aggregation inhibitor. [29] [30] 

As used in the Ayurvedic tradition, Nagara has reported anti-inflammatory properties and has been used in some inflammatory conditions such as arthritis. [31][32]  Nagara was reported to be effective against pain and swelling in more than three-quarters of the 56 patients studied (28 with rheumatoid arthritis, 18 with osteoarthritis and 10 with muscular discomfort). [33] None of the patients reported adverse effects during the period of Nagara consumption which ranged from 3 months to 2.5 years. It has been suggested that at least one of the mechanisms by which Nagara has anti-inflammatory effects is the inhibition of prostaglandin and leukotriene biosynthesis. [34] 

Interaction and Depletions

Interaction with other Herbs

No documentation.

Interaction with Drugs

Based on pharmacology, constituents in Z. officinale may inhibit platelet aggregation which may alter the effects of medications used for this purpose. [30][35] 

Based on pharmacology, caution should be used in patients with bleeding disorders. [36] 

Precautions and Contraindications

Side effects

Some instances of gastric upset have been reported. [37]

Pregnancy

While considered useful during pregnancy, use of any herb is cautioned during pregnancy and nursing.

Age limitation

No documentation.

Adverse reaction

No documentation.

Read More

  1) Cultivation

  2) Medicinal Herbs

  3) Essential Oil

  4) South Africa Herbs

References