Lemongrass

• How It Works

  Lemongrass has antioxidant, anticancer, and antimicrobial properties, but it has not been studied in cancer patients.

  There are over 140 species of lemongrass that are prevalent in many parts of Africa and Asia. It is widely used as a flavoring agent in Asian cuisine, in perfumery, and as an insect repellent. Lemongrass has also been traditionally used in folk medicine to treat anxiety, gastrointestinal problems, and to induce sleep. These effects have mostly been shown in animal studies. Lab studies showed that lemongrass can lower blood pressure, and has anti-inflammatory, antioxidant, and anticancer properties. More research is needed to confirm such effects in humans.

• Purported Uses
  • To treat or prevent cancer
    Although lab and animal studies showed that compounds in lemongrass can inhibit tumor growth or cause cancer cell death, human data are lacking.
  • To lower blood pressure
    Lab studies suggest that lemongrass can lower blood pressure by relaxing blood vessels. Human studies are needed.
  • To improve sleep
    Animal studies have shown that lemongrass injections can produce sedative effects. However, drinking lemongrass tea does not have the same effect in humans.
  • To prevent infections
    Lab studies show that lemongrass has activity against various microorganisms. A clinical trial of HIV/AIDS patients with oral thrush indicated that lemongrass is an effective antifungal treatment. It may also be helpful in addition to mainstream therapies for chronic gum disease.
  • To reduce inflammation
    Lab and animal studies showed favorable results, but human data are lacking.
  • To reduce anxiety
    Clinical studies show that lemongrass tea does not lower anxiety or produce calming effects. However, briefly breathing in lemongrass essential oil might speed recovery from some types of anxiety. More studies are needed to confirm this effect.
• Do Not Take If
  • You are undergoing chemotherapy: Lemongrass can act as an antioxidant and may reduce the effectiveness of some chemotherapy agents.
  • You are taking drugs that are glutathione-S-transferase substrates: Although no interactions have been reported, ingesting quantities of lemongrass over standard culinary use may increase the risk of side effects of these drugs.
  • You are taking drugs that are cytochrome P450 substrates: Although no interactions have been reported, ingesting quantities of lemongrass over standard culinary use may increase the risk of side effects of these drugs.
  • You are pregnant: Citral and myrcene in lemongrass caused birth defects in rats.
• Side Effects

  Oral: Dizziness, drowsiness, dry mouth, excess urination, and increased appetite.
  In high doses, essential oil of lemongrass can damage liver and stomach mucous membranes.
  Excessive intake of lemongrass tea may also affect kidney function.

  Topical: Skin rash with the use of lemongrass essential oils

  Case report
  Delayed skin rash from both topical and oral use: In a 52-year-old massage therapist who also practiced aromatherapy with essential oils including lemongrass. Her rash also came back after she drank lemongrass tea.

• Scientific Name

  Cymbopogon citratus, Cymbopogon flexuosus

• Clinical Summary

  The genus Cymbopogon consists of several lemongrass species ⁽¹⁾ that are prevalent in the tropical regions of Africa and Asia, ⁽²⁾ including C. citratus (West Indian) and C. flexuosus (East Indian). Lemongrass is widely used as a flavoring agent in Asian cuisine, in perfumery, and as an insect repellent ⁽⁶⁾. It has been used in folk medicine as a sedative ⁽³⁾, to reduce gastrointestinal problems ⁽⁴⁾, and for its central nervous system-depressant effects ⁽⁵⁾. It is traditionally consumed as a tea and used in aromatherapy.

  In vitro, lemongrass exhibits antimicrobial ^{(21) (23) (24)}, antibiofilm ⁽²⁵⁾, anti-inflammatory ⁽²⁶⁾, neuroprotective ⁽²⁷⁾, vasorelaxant ⁽¹⁰⁾, and antidiabetic effects ⁽²⁸⁾. Lemongrass extracts and constituents have shown antioxidant, antiproliferative, and apoptotic activity ^{(8) (9) (29) (30)}. Animal models also suggest anticancer ⁽³¹⁾, anti-inflammatory ⁽³²⁾, anti-allergic ^(33) (34), and anxyolitic activity ⁽³⁵⁾, as well as protective effects on various organ systems ^{(36) (37) (38) (39) (40)}.

  In human pilot studies, lemongrass essential oil formulations were a helpful adjunct to periodontal therapy for patients with chronic periodontitis ⁽⁴¹⁾ and helped reduce oral thrush in HIV-positive patients ⁽⁷⁾. Lemongrass demonstrated antifungal activity against pityriasis versicolor, but was not as effective as ketoconazole ⁽⁴²⁾.

  In other studies evaluating lemongrass tea consumption, erythropoiesis-boosting effects were observed, suggesting possible uses in the treatment or prevention of anemia  ⁽⁴³⁾. However, lemongrass tea may also produce dose- and time-dependent adverse effects on renal function  ⁽⁴⁴⁾. Other studies have not found lemongrass tea ingestion to reduce anxiety or to benefit sleep ⁽⁵⁾. However, brief inhalation of lemongrass essential oil may help to accelerate recovery from some types of anxiety compared with controls ⁽⁴⁵⁾. More studies are needed to confirm this effect.

  Although lemongrass and its constituents induced apoptosis in some cancer cell lines ^{(11) (12) (29) (30) (31)}, they have not been studied in cancer patients.

• Food Sources

  Lemongrass is used to flavor many foods and beverages. The dried leaves are used to make tea.

• Purported Uses
  • Anticancer
  • Anti-inflammatory
  • Antimicrobial
  • Anxiolytic
  • Sedative
  • Vasorelaxation
• Mechanism of Action

  Chlorogenic acid, isoorientin, and swertiajaponin were identified as the active constituents in lemongrass that possess antioxidant properties to prevent endothelial dysfunction via a nitric oxide-independent vasodilatador effect on blood vessels ⁽⁴⁶⁾. In vitro, anti-inflammatory effects of lemongrass occur through inhibition of IL-1beta ⁽²⁶⁾, and proteasome and nuclear factor-kappaB pathways by chlorogenic acid ⁽⁴⁷⁾. In rat cerebellar granule neuron cultures, neuroprotective effects were attributed to antiapoptotic activity that occurred with cell cycle arrest in the G0G1 phase ⁽²⁷⁾.

  In animal models, anti-allergic and anti-inflammatory effects were attributed to the major constituents citral and geranial ⁽³³⁾. The anti-inflammatory effects of citral were further attributed to PPAR-gamma activation ⁽³⁸⁾. Lemongrass inhibits release of the inflammation marker myeloperoxidase from neutrophils and suppresses IL-6 and IL-1alpha production in mice peritoneal macrophages ⁽¹³⁾. A lemongrass hexane extract modulated allergic asthma via inhibition of nuclear factor kappa B activation ⁽³⁴⁾. Analgesic effects by the constituent citronellol are attributed to inhibition of peripheral mediators as well as central inhibitory mechanisms ⁽²²⁾. Anxiolytic activity of lemongrass appeared to be mediated by the GABAergic system ⁽³⁵⁾. It also altered onset and duration of convulsions and potentiated sleep time through GABAergic mechanisms ⁽³⁾, and increased seizure threshold by blocking seizure propagation ⁽¹⁵⁾.

  In humans, the erythropoiesis-boosting effects produced with lemongrass tea consumption are likely due to its nutritional constituents and antioxidant and pharmacologic properties  ⁽⁴³⁾. As aromatherapy to revert reactive anxiety, lemongrass essential oil appears to act through the olfactory or nose-to-brain pathways to restore homeostasis ⁽⁴⁵⁾.

  Several constituents in lemongrass demonstrate anticancer activity. Isointermedeol upregulates tumor necrosis factor receptor 1 leading to apoptosis through the extrinsic Fas pathway ^(2) (11). It also increases mitochondrial expression and activation of caspase-9 via the intrinsic cell death pathway. Citral induced apoptosis via caspase-3 enzymatic activity in human leukemia and breast cancer cells ⁽⁸⁾, and induced glutathione S-transferase (GST) through an electrophilic interaction with glutathione in rat liver epithelial cells. GST functions in cell detoxification by rescuing cells from oxidative damage and carcinogenic compounds ^(9) (12). Cytotoxicity was attributed to the presence of an unsaturated aldehyde group, which is specific to the geranial isomer of citral ⁽⁹⁾. Polysaccharides from lemongrass produced cytotoxic and apoptotic effects in cervical and prostate carcinoma cells via caspase 3 upregulation and Bcl-2 downregulation followed by cytochrome c release ⁽²⁹⁾, and antitumor and immunomodulatory activities in sarcoma-180 tumor cells were attributed to immunoenhancement rather than direct cytotoxicity ⁽³¹⁾.

• Contraindications
  • Because of its antioxidant potential, lemongrass may interfere with the actions of some chemotherapeutic agents.
  • Lemongrass should be avoided during pregnancy as high doses of citral and myrcene caused birth defects in rats ^(16) (17).
• Adverse Reactions

  Oral: Dizziness, drowsiness, dry mouth, excessive urination, and increased appetite ^(5) (7).

  In high doses, the essential oil of C. citratus can damage liver and stomach mucosae ⁽¹⁸⁾. Excessive ingestion of lemongrass tea may also have adverse effects on renal function  ⁽⁴⁴⁾.

  Topical: Contact dermatitis ⁽⁴⁸⁾.

  Case report
  Delayed contact dermatitis (topical and oral): In a 52-year-old massage therapist who also practiced aromatherapy with essential oils including lemongrass. Her cutaneous symptoms also recurred following ingestion of lemongrass tea ⁽⁴⁹⁾.

• Herb-Drug Interactions
  • Glutathione-S-transferase (GST) substrates: Citral, found in lemongrass essential oil, was shown to induce GST ⁽⁹⁾.
  • Cytochrome P450 substrates: Beta-myrcene in lemongrass can interfere with cytochrome P450 liver enzymes ^(19) (20), although lemongrass-prescription drug interactions have not been reported.
• References

  1. Ganjewala D and Luthra R. Essential oil biosynthesis and regulation in the genus Cymbopogon. Nat Prod Commun 2010;5(1):163-72.

  2. Sharma PR, et al. Anticancer activity of an essential oil from Cymbopogon flexuosus. Chem Biol Interact 2009; 179(2-3):160-8.

  3. Silva MR, et al. Comparative anticonvulsant activities of the essential oils (EOs) from Cymbopogon winterianus Jowitt and Cymbopogon citratus (DC) Stapf. in mice. Naunyn Schmiedebergs Arch Pharmacol 2010; 381(5):415-26.

  4. Carlini EA, et al. Pharmacology of lemongrass (Cymbopogon citratus Stapf). I. Effects of teas prepared from the leaves on laboratory animals. J Ethnopharmacol 1986; 17(1):37-64.

  5. Leite JR, et al. Pharmacology of lemongrass (Cymbopogon citratus Stapf). III. Assessment of eventual toxic, hypnotic and anxiolytic effects on humans. J Ethnopharmacol 1986; 17(1):75-83.

  6. Nerio LS, Olivero-Verbel J, Stashenko E. Repellent activity of essential oils: a review. Bioresour Technol 2010;101(1):72-8.

  7. Wright SC, Maree JE, Sibanyoni M. Treatment of oral thrush in HIV/AIDS patients with lemon juice and lemon grass (Cymbopogon citratus) and gentian violet. Phytomedicine 2009;16(2-3):118-24.

  8. Chaouki W, et al. Citral inhibits cell proliferation and induces apoptosis and cell cycle arrest in MCF-7 cells. Fundam Clin Pharmacol 2009;23(5):549-56.

  9. Nakamura Y, et al. A phase II detoxification enzyme inducer from lemongrass: identification of citral and involvement of electrophilic reaction in the enzyme induction. Biochem Biophys Res Commun 2003;302(3):593-600.

  10. Runnie I, et al. Vasorelaxation induced by common edible tropical plant extracts in isolated rat aorta and mesenteric vascular bed. J Ethnopharmacol 2004; 92(2-3):311-6.

  11. Kumar A, et al. An essential oil and its major constituent isointermedeol induce apoptosis by increased expression of mitochondrial cytochrome c and apical death receptors in human leukaemia HL-60 cells. Chem Biol Interact 2008; 171(3):332-47.

  12. Dudai N, et al. Citral is a new inducer of caspase-3 in tumor cell lines. Planta Med 2005;71(5):484-8

  13. Sforcin JM, et al. Lemongrass effects on IL-1beta and IL-6 production by macrophages. Nat Prod Res 2009;23(12):1151-9.

  14. Ernst E. Herbal remedies for anxiety – a systematic review of controlled clinical trials. Phytomedicine 2006;13(3):205-8.

  15. Blanco MM, et al. Neurobehavioral effect of essential oil of Cymbopogon citratus in mice. Phytomedicine 2009;16(2-3):265-70.

  16. Delgado IF, Carvalho RR, Nogueira AC, et al. Study on embryofoetotoxicity of b-myrcene in the rat. Food and Chemical Toxicology 1993;31(1):31-35.

  17. Nogueira AC, Carvalho RR, Souza CA, Chahoud I, Paumgartten FJ. Study on the embryofeto-toxicity of citral in the rat. Toxicology 1995;96(2):105-113.

  18. Fandohan P, Gnonlonfin B, Laleye A, et al. Toxicity and gastric tolerance of essential oils from Cymbopogon citratus, Ocimum gratissimum and Ocimum basilicum in Wistar rats. Food Chem Toxicol 2008;46(7):2493-2497.

  19. De-Oliveira AC, Ribeiro-Pinto LF, Paumgartten JR. In vitro inhibition of CYP2B1 monooxygenase by beta-myrcene and other monoterpenoid compounds. Toxicol Lett 1997;92(1):39-46.

  20. De-Oliveira AC, Ribeiro-Pinto LF, Otto SS, Goncalves A, Paumgartten FJ. Induction of liver monooxygenase by beta-myrcene. Toxicology 1997;124(2):135-140.

  21. Chaudhari LK, Jawale BA, Sharma S, Sharma H, Kumar CD, Kulkarni PA. Antimicrobial activity of commercially available essential oils against Streptococcus mutans. J Contemp Dent Pract.2012 Jan 1;13(1):71-4.

  22. Brito RG, Guimarães AG, Quintans JS, et al. Citronellol, a monoterpene alcohol, reduces nociceptive and inflammatory activities in rodents.J Nat Med. 2012 Oct;66(4):637-44.

  23. Warnke PH, Lott AJ, Sherry E, et al. The ongoing battle against multi-resistant strains: in-vitro inhibition of hospital-acquired MRSA, VRE, Pseudomonas, ESBL E. coli and Klebsiella species in the presence of plant-derived antiseptic oils. J Craniomaxillofac Surg. Jun 2013;41(4):321-326.

  24. Vazquez-Sanchez D, Cabo ML, Rodriguez-Herrera JJ. Antimicrobial activity of essential oils against Staphylococcus aureus biofilms. Food Sci Technol Int. Oct 3 2014.

  25. Adukwu EC, Allen SC, Phillips CA. The anti-biofilm activity of lemongrass (Cymbopogon flexuosus) and grapefruit (Citrus paradisi) essential oils against five strains of Staphylococcus aureus. J Appl Microbiol. Nov 2012;113(5):1217-1227.

  26. Salim E, Kumolosasi E, Jantan I. Inhibitory effect of selected medicinal plants on the release of pro-inflammatory cytokines in lipopolysaccharide-stimulated human peripheral blood mononuclear cells. J Nat Med. Jul 2014;68(3):647-653.

  27. Tayeboon GS, Tavakoli F, Hassani S, et al. Effects of Cymbopogon citratus and Ferula assa-foetida extracts on glutamate-induced neurotoxicity. In Vitro Cell Dev Biol Anim. Oct 2013;49(9):706-715.

  28. Boaduo NK, Katerere D, Eloff JN, et al. Evaluation of six plant species used traditionally in the treatment and control of diabetes mellitus in South Africa using in vitro methods. Pharm Biol. Jun 2014;52(6):756-761.

  29. Thangam R, Sathuvan M, Poongodi A, et al. Activation of intrinsic apoptotic signaling pathway in cancer cells by Cymbopogon citratus polysaccharide fractions. Carbohydr Polym. Jul 17 2014;107:138-150.

  30. Halabi MF, Sheikh BY. Anti-proliferative effect and phytochemical analysis of Cymbopogon citratus extract. Biomed Res Int. 2014;2014:906239.

  31. Bao XL, Yuan HH, Wang CZ, et al. Polysaccharides from Cymbopogon citratus with antitumor and immunomodulatory activity. Pharm Biol. Jan 2015;53(1):117-124.

  32. Boukhatem MN, Ferhat MA, Kameli A, et al. Lemon grass (Cymbopogon citratus) essential oil as a potent anti-inflammatory and antifungal drugs. Libyan J Med. 2014;9:25431.

  33. Mitoshi M, Kuriyama I, Nakayama H, et al. Suppression of allergic and inflammatory responses by essential oils derived from herbal plants and citrus fruits. Int J Mol Med. Jun 2014;33(6):1643-1651.

  34. Santos Serafim Machado M, Ferreira Silva HB, Rios R, et al. The anti-allergic activity of Cymbopogon citratus is mediated via inhibition of nuclear factor kappa B (Nf-Kappab) activation. BMC Complement Altern Med. 2015;15:168.

  35. Costa CA, Kohn DO, de Lima VM, et al. The GABAergic system contributes to the anxiolytic-like effect of essential oil from Cymbopogon citratus (lemongrass). J Ethnopharmacol. Sep 1 2011;137(1):828-836.

  36. Ullah N, Khan MA, Khan T, et al. Cymbopogon citratus protects against the renal injury induced by toxic doses of aminoglycosides in rabbits. Indian J Pharm Sci. Mar 2013;75(2):241-246.

  37. Rahim SM, Taha EM, Al-janabi MS, et al. Hepatoprotective effect of Cymbopogon citratus aqueous extract against hydrogen peroxide-induced liver injury in male rats. Afr J Tradit Complement Altern Med. 2014;11(2):447-451.

  38. Shen Y, Sun Z, Guo X. Citral inhibits lipopolysaccharide-induced acute lung injury by activating PPAR-gamma. Eur J Pharmacol. Jan 15 2015;747:45-51.

  39. Sagradas J, Costa G, Figueirinha A, et al. Gastroprotective effect of Cymbopogon citratus infusion on acute ethanol-induced gastric lesions in rats. J Ethnopharmacol. Sep 15 2015;173:134-138.

  40. Rahim SM, Taha EM, Mubark ZM, et al. Protective effect of Cymbopogon citratus on hydrogen peroxide-induced oxidative stress in the reproductive system of male rats. Syst Biol Reprod Med. Dec 2013;59(6):329-336.

  41. Warad SB, Kolar SS, Kalburgi V, et al. Lemongrass essential oil gel as a local drug delivery agent for the treatment of periodontitis. Anc Sci Life. Apr 2013;32(4):205-211.

  42. Carmo ES, Pereira Fde O, Cavalcante NM, et al. Treatment of pityriasis versicolor with topical application of essential oil of Cymbopogon citratus (DC) Stapf – therapeutic pilot study. An Bras Dermatol. May-Jun 2013;88(3):381-385.

  43. Ekpenyong CE, Daniel NE, Antai AB. Bioactive natural constituents from lemongrass tea and erythropoiesis boosting effects: potential use in prevention and treatment of anemia. J Med Food. Jan 2015;18(1):118-127.

  44. Ekpenyong CE, Daniel NE, Antai AB. Effect of lemongrass tea consumption on estimated glomerular filtration rate and creatinine clearance rate. J Ren Nutr. Jan 2015;25(1):57-66.

  45. Goes TC, Ursulino FR, Almeida-Souza TH, et al. Effect of lemongrass aroma on experimental anxiety in humans. J Altern Complement Med. Sep 14 2015.

  46. Campos J, Schmeda-Hirschmann G, Leiva E, et al. Lemon grass (Cymbopogon citratus (D.C) Stapf) polyphenols protect human umbilical vein endothelial cell (HUVECs) from oxidative damage induced by high glucose, hydrogen peroxide and oxidised low-density lipoprotein. Food Chem. May 15 2014;151:175-181.

  47. Francisco V, Costa G, Figueirinha A, et al. Anti-inflammatory activity of Cymbopogon citratus leaves infusion via proteasome and nuclear factor-kappaB pathway inhibition: contribution of chlorogenic acid. J Ethnopharmacol. Jun 21 2013;148(1):126-134.

  48. Uter W, Schmidt E, Geier J, et al. Contact allergy to essential oils: current patch test results (2000-2008) from the Information Network of Departments of Dermatology (IVDK). Contact Dermatitis. Nov 2010;63(5):277-283.

  49. Bleasel N, Tate B, Rademaker M. Allergic contact dermatitis following exposure to essential oils. Australas J Dermatol. Aug 2002;43(3):211-213.